After you start playing Obra Dinn, you'll find a little bit of a tutorial in which it tells you that when a character's face is blurred, it's impossible to identify him/her. However, when that face is no longer blurry, there is enough evidence hidden within all the unlocked memories to positively identify the person. That is, without any guess-work at all, you can absolutely find evidence that will let you ID the person.

But, if you're like me, you probably haven't found that evidence for each individual sailor. Not to mention, the way the game forces you along by means of following a new smoke-cloud almost every time you complete a memory, it can be hard to pinpoint just which memories allowed you to pass the threshold from "blurry" to "not-blurry." At these times, it's very tempting to simply "brute-force" your way through the game. That is, keep guessing randomly until you manage to get three people right and it type-sets the answers.

This guide is meant to tell the reader how you're "supposed" to find the answer. Ideally, it's for a person who completed the game with a full book, but who might have guessed several of the identities, to look back and say: "Oh, that's what I was supposed to do?" But a player who has not yet finished the game might also read part of this guide for hints on how to properly deduce the identities of each character. If you're looking for just a guide that outright solves the game for you, please do not rely on this guide. I will reveal every individual character's identity, but I'm not using pictures. Furthermore I'm doing it in a very long-winded manner. You would be much better served, if you're just looking for a solutions sheet, to read one of the other equally helpful guides written by the community. They're very useful for this purpose.

That said, let's begin.

a. The first memory has four characters. One is holed up and three are outside. One of the men outside calls out to the man inside as "Captain!" Looking at the crew list, there is only one captain. You can therefore immediately identify him by his rank and mark him.

b. The second and third memories don't give you any new information used to identify the men. You should simply record how they die and who killed them and move on.

c. The captain's own death involves him talking to Abigail's dead body, and he talks about killing her brother. Checking the crew list, you can see Abigail has the same last name as the captain, and she's therefore his wife. Her middle name should be her maiden name. You can then find that one man on the crew has the same last name as her middle name. That is her brother and you can now identify him with 100% certainty.

d. The memory of Abigail's death is simple enough. You already know who she is, and since this is her death memory, you can identify her. Maybe a little more tricky is identifying "Martin" who she calls out to. There are several men on the ship, so who can you say who she was talking with, definitively? Check for a "Martin" on the crew list. There is only one, the third mate. You've already identified the captain and the first mate. The third mate is someone who is in a position of authority, and his clothes are probably as nice as the captain's and the first mate's. There's one man close by who fits this description, and he is Martin.

At the same time, you can see in the corner near the passenger cabins two other women. Just from looking at them, their faces are unblurred. If you scan the entire crew list, you'll see there are only four women on the ship. Abigail you've already identified. Another of them is clearly Chinese/Formosan. That leaves Jane and Emily, so you can identify that these women are Jane and Emily. But, which is which? The clue is very subtle. Emily is simply listed as "Emily" but Jane is listed as "Miss Jane." A woman who is given the prefix of "Miss" means they are unmarried. Look closely at the women. Look at their left hands. One of them is clearly wearing a ring around their left ring finger, indicating they are married. The woman without a ring must be "Miss Jane," so that means the other woman must be Emily.

e. The memory of one sailor being torn apart. We can see he's on the top of the ship, so he is likely a topman and not a seaman. Furthermore, he has very distinctive tattoos all over his body. Look at the nationalities of all the men. One of them is from New Guinea, where they have very distinctive tribal tattoos. This man can therefore be identified as Maba, despite the fact that no one calls him by name and we don't see any other reference to him, yet.

f. A man is stabbed trying to escape in a rowboat. He is called out to as "Paul." There is only one man named Paul on the crew list, and he is easily identified.

g. A man is knifed in the back, crawls into a room to die while the first mate tries to comfort him. He mentions "Pete." He therefore cannot be Pete. He talks about "trying to pull Pete back in". There's a previous memory of a man exploding on deck while being grappled by the squid monster, and the same character dying from the knife is holding a rope that the exploding man is trying to hold onto. We can therefore conclude the exploding man is "Pete." At the same time, we can see he's a midshipman. The stabbed man also crawled into a midshipman cabin. We can't positively ID the stabbed man, but we can say he's likely a midshipman, since his clothes are relatively similar and he seems very close to this "Pete."
At the same time, the first mate calls on "Brennan" by name to come help him. There's several other dead people outside, and one person alive who would be the only person available to be called. This is "Brennan," and it's also the person the captain kills from the second memory.

h. The memory of the one-armed person talking to two others can be easily identified. He uses the word "Verdammt," which is the German word for "damn". Furthermore, he asks "Where is my Frenchman?" Checking the crew list, you can see there are only two people from a german-speaking nation, Austria. One of them has a french mate. The frenchman is the Bosun's mate, so the one-armed man must be the Bosun. We don't know who the Bosun's mate is by their picture, yet, but we can keep in mind how he dies from what the characters say.

At this point, the player has a little more freedom in what memories they pursue, so I will be using a simple list.

1. Captain Witterel, solved already.
2. First Mate, solved already.
3. Second Mate Nichols. In the memory of Pasqua being murdered, he can be heard being referred to by name. Alternatively, someone calls him by name when they are in the rowboats.
4. Third Mate Martin. Solved already.
5. 4th mate John Davies. In the memory where Second Mate Nichols rows back to the Obra Dinn and is shot, you can see a man watching from a window. If you line his position up with the ship's map, you can see he's looking from the window of the Fourth Mate's private room. He is therefore the fourth mate. He's also dressed nicely like the other mates and the captain. (You could also possibly identify him because he's the only 'mate' who hasn't been accounted for, but the game doesn't unblur him until that scene.)
6. Bosun Alfred. Solved already.
7. Bosun's Mate Charles Miner. The Bosun's job is to act as a foreman. He can be seen watching over the crew at times when the Bosun himself isn't present. He is also very close to the Bosun whenever they share scenes. Furthermore he has on a striped shirt, which was associated with the French navy. He's never heard speaking, so he can't be identified by an accent.
8. Surgeon Henry Evans. He's present giving a diagnosis on the sick crew members' health, and he's being consulted by the officers instead of the other guy in the room, meaning he's the one in charge.
9. Surgeon's Mate James Wallace. He's present in the surgeon's room with the surgeon, but he's not the person asked for their opinion on medical matters. This means he's the assistant, not the actual surgeon. You can alternatively see him lounging around or doing some menial cleaning up.
10. Carpenter Winston Smith. He can be seen in the carpentry room holding a hammer. He's also the first one to step out and investigate when the mermaids are being taken in. Furthermore, the other person in the carpentry room calls him 'Boss'. Therefore, he is the one in charge.
11. Carpenter's Mate Marcus Gibbs. He's with the carpenter handling tools, and he refers to the other man as 'boss'.
12. Cook Thomas Sefton. He makes a joke about offering to cook the mermaids in his death scene. He also carries around a two-pronged fork for cooking.
13. Butcher Emil O'Farrell. He can be seen showing the midshipmen how to butcher the cow. He also has an irish accent. He can be seen standing with the cook in the scene of the execution.
14. Gunner Christian Wolff. He's referred to by name when the Captain orders him to carry out the execution. He also has a german accent.
15. Gunner Mate Olus Wiater. He can be seen handling guns with the Gunner. He also has a vaguely east european accent, but he's obviously not one of the Russians because he's not dressed like a seaman.
16. Purser Duncan McKay. He can be seen hiding in the Purser's office while the crab monster fight is going on, if you look through the slats behind the frame. Furthermore he's carrying papers when he's in an escape rowboat. Furthermore he has a scottish accent for his one line.
17. Helmsman Finley Dalton. He has no speaking lines, and he's only in a few scenes, but you're supposed to be able to guess it's him because he's standing next to the wheel that controls the ship's movements in the sketch and the few scenes he does appear in. He's technically unblurred from the very beginning.
18. Artist Edward Spratt. He's also unblurred from the very beginning, but he's not "in" the sketch, just as a pair of initials, which are easily matched to his name and occupation as 'artist'. As long as you bring up his profile when you're looking at the actual man, it won't show his face, but will instead show the initials.
19. Abigail, solved already.
20. Nunzio Pasqua. It's stated he was murdered, and he has an italian accent when no one else on the ship is Italian.
21. Emily Jackson. She's a woman, and she's not Abigail, nor is she the formosan woman. She is likely married and is wearing a wedding ring.
22. Miss Jane Bird. There's nothing to differentiate Jane Bird from Emily Jackson, except that referring to Jane Bird as "Miss" means she's unmarried. Emily has a wedding ring, Jane does not. Those are the only two women left on the ship after Abigail is identified and you rule out the formosan woman.
23. Lim Bun-Lan. She is referred to as "Miss Lim" by another formosan directly.
24. Sia It-Beng. Lim Bun-Lan will call him by name in one scene on the rowboat.
25. Tan Chioh. He's the only Chinese passenger not directly identified, but once the other three are identified, you can deduce it is him.
26. Lau Hok-Seng. He's identified by name when he's executed. He can also be seen injured by Nichols in Pasqua's murder scene.
27. Ship's Steward Zungi Sathi. He's never directly identified, but you can compare his clothing to the other ship stewards and deduce he's a steward. You may also determine he's the steward who looks most like he may be Indian out of all of them. Even if that's difficult to tell, after the others are identified by being associated with the captain or one of the mates, process of elimination reveals it is him and he must be the ship's steward. He has no speaking lines other than some hurried breathing, so he can't be deduced by an accent or language.
28. Captain's steward Filip Dahl. He's referred to by the captain when he says "Twenty years my steward!" Furthermore, he speaks a little bit of Swedish, which reveals his national origins.
29. 1st mate's steward Paul Moss. He's referred to as "Paul" in "Paul, watch out!" right before he's killed. Solved already.
30. 2nd Mate's Steward Samuel Galligan. He's with Nichols when they are in the rowboat escaping with the stolen treasure and captives. He's wearing a Steward's outfit. He has an irish accent when he speaks. He can be seen whispering to second mate Nichols in the execution scene, if not the artist's sketch.
31. 3rd Mate's Steward Roderick Andersen. In the scene of Edward Splatt's death, you can see him carrying a plate of food with the 3rd mate. He's wearing a steward's uniform and he's "seeing to the 3rd mate's needs." You can therefore determine he's the steward for the 3rd mate.
32. 4th mate's steward Davey James. He's another steward wearing the uniform. In the execution scene of Hok-Seng Lau, you can see him standing with the 4th mate covering his ears. This is enough to associate him with the 4th mate.
33. Midshipman Peter Milroy. He's referred to by another midshipmen when they describe "Tell Pete's mom I tried to pull him back," and you can see he does have a rope tied around him that's being pulled on by that person. He's wearing a midshipman uniform. You can see him with other three midshipman in the cow being butchered scene, and he's not "Charlie".
34. Midshipman Thomas Lanke. He's uniformed like a midshipman, he's referred to as "fresh" by the Gunner's Mate, and midshipman are inexperienced officers-in-training as explained by the glossary. He's not "Pete" because he claims to have tried to save Pete. He's also not "Charlie" because he's not the one throwing up in the cow butcher scene. That leaves only Thomas as the only midshipman left.
35. Midshipman Charles Hershtik. He's referred to by name "Charlie" in the cow butchering scene. The Bosun's Mate is also named Charles, but this Charles is dressed like the other midshipmen, and they clearly are being casual with him when they call him "Charlie," indicating they're all the same rank. He therefore can't be the Bosun's Mate.

36. Omid Gul. In the scene of Edward Spratt dying, you can see a hammock with his number and an unusual curved sword. This is a scimitar and it's associated with middle eastern countries and Omid Gul is listed as a persian. He can also be seen carrying this particular sword in some scenes. Lastly, he wears a turban which someone from Persia could wear. Someone from India could also wear a turban, but you can identify the indian seamen, and Omid is clearly a seaman and not a steward so he can't be Zungi. That means he must be Omid.
37. Timothy Buteman. In the scene of Syed dying, you can find Timothy's hammock with his number on it. His arm is visible with a distinct tattoo of a woman. You can see his arm and this tattoo in his death scene and identify him.
38. Li Huang. Except for Lee Wei, you must identify all other Chinese sailors by comparing their shoes and legs that are sticking out of their hammocks in the Syed death scene. This can be difficult because this section of the boat is dark. His shoes have toe-cover only, a darker/black tint compared to Zhang Jie, and don't have that sort of off-tint look to his legs. He's struck by lightning while climbing on the rigging.
39. Zhang Jie. He can be identified by his toe-shoes. He has on shoes that are a lighter/white tint than Hong Li, and sort of 'stockings' that gives a off-even striped tint to them. He's decapitated/strangled by one of the crab monsters. Comparing him to Li Huang is best done in the lightning-strike scene as they are both very clearly shown.
40. Hong Li. He can be identified by his shoes. He has shoes that have a tongue/cover that go all the way to his ankle. Zhang Jie and Li Huang don't have this type of shoe. Lee Wei survives until the Doom and so he can't be Hong Li, whose hammock disappears. That leaves Hong Li as the Chinese sailor with the ankle-length all-round shoes. (He's the sailor who goes off with Nichols and dies in the Calling.)
41. Lee Wei. It's not necessary to identify him by his shoes. If you look in Syed's death scene, you will see that his hammock is with the other Chinese sailors. In Edward Spratt's death scene, you can see all the hammocks of the Chinese sailors are gone except his. You can identify him this way as the last surviving Chinese sailor.
42. Nicholas Botterill. In the scene chronologically after he's killed, someone says "They've already done for Nick!" meaning, they (the monsters) have already killed Nick. He can therefore be identified by that as there's no other Nick. (Second mate Nichols is long dead by this point.)
43. Maba. He's from New Guinea and has those tattoos. He could also possibly be identified from his hammock still being around in Edward Spratt's scene, but that's how you should identify him. Solved already.
44. Lewis Walker. He's a topman, as seen because he's with other topmen in the lightning-strike scene, and he's usually crawling around on the rigging. He's not Russian, or Chinese, or Persian, and he's not Nicholas or Timothy Buteman. That leaves only one English topman, and it's him. As a further clue, his is the only hammock left in the gun deck in the present, suggesting he lived through the Doom.
45. Leonid Volkov. He's Russian, but also a topman because he's with the other topmen in the lightning-strike scene. The other two Russians are not topmen. He's also clearly not a officer so he can't be the Polish Gunner's Mate.
46. Alarcus Nikishin. He's Russian because he's sitting with the other two Russians in the card-game in Syed's death, but he's not Leonid, nor is he Aleksei. That means he must be Alarcus.
47. Aleksei Toporov. He's Russian, but he has a distinctive satchel next to his hammock, and there's a tobacco pipe in the satchel. He can be seen carrying this satchel and smoking this pipe in the scene where Timothy is shot, and when they're on the rowboat. This is Aleksei.
48. Nathan Peters. He shares a last name with another sailor, and he claims "You killed my brother!" indicating the two were brothers and he must be one half of them. His hammock number can be seen in scenes where you can see the hammocks, but you can't see the hammock of the other brother, number 60. That means number 60 is the one who died, and Nathan is therefore the brother still alive.
49. Lars Linde. He's called "Dane" by Nathan Peters, and he's the only person from Denmark on the crew list. You can also hear him speak Danish.
50. John Naples. He's called "John" by the surgeon in his death scene. He's also clearly a seaman and not an officer, so he can't be the fourth mate.
51. Renfred Rajub. He can be seen dying in his hammock with the number on it in Syed's death scene.
52. Abraham Akbar. His hammock number is x'd out, but he's sitting in it, and he is the only other Indian after the other three seamen are accounted for.
53. William Wasim. His hammock is empty because he is trying to help Syed in the Syed death scene. He also speaks Hindi.
54. Solomon Syed. He's referred to by name as 'Syed', he's sleeping in his own hammock with his number, and the surgeon says he must've picked up his illness from the "lascar house." A lascar is a sailor from India (and other places) serving on a european ship.
55. Hamadou Diom. You can only identify him after you've identified all of the other sailors and he and Booth are the only seamen left. Booth is English and would speak with an English accent and Diom is from Sierra Leone. Diom therefore has no speaking lines and he's the one killed with Tan Chioh. He also has a dark skin tone (in his death memory, not so much in the sketch) which suggests an african origin, and he's not one of the other crew members who has a similar tone. (It's hard to tell with the graphics, but he's clearly not Booth or the carpenter.) Sierra Leone is in Africa. His hammock is gone after he dies and cannot be seen in the Edward Spratt death scene.
56. Henry Brennan. In the scene where midshipman Thomas dies, the 1st mate yells for Brennan to bring the surgeon's kit. Besides Lewis, there's only one other man still alive in that scene, and it's Brennan. Brennan has his hand over his ear when his name is called, further supporting that he's the one being referred to as "Brennan" in that scene. Solved already.
57. Alexander Booth. You can't identify Booth by his hammock or anything else. You can only identify him after every other seaman is identified. You can hear him speak when Linde is killed and he has an English accent. The only other person in the scene (besides Nathan, and Booth is not Nathan) is the purser, who has a scottish accent. He therefore can't be from Sierra Leone, so he must be English, and you can identify him as Booth. He also still has a hammock up in Edward Spratt's death scene, indicating he was still alive until that chapter, so he can't be Diom. Furthermore, in the Edward Spratt scene, the only persons who have a hammock but aren't in the scene are Nathan Peters, Booth, Lars, and Omid. Once you determine Omid isn't among the deserters, and that the other man is Duncan, that leaves only Booth and he becomes unblurred.
58. Patrick O'Hagan. He has a clear irish accent, and he's referred to by 2nd mate steward Galligan when he asks him "O'Hagan, you still breathing?" O'Hagan has died by this point and he can be identified because he's not one of the Russians, and he's not Chinese.
59. George Shirley. Shirley has his hammock set up with the four Chinese sailors. He can be seen sitting with Lee Wei, but his hammock number is covered. You can identify him by comparing the hammocks in that scene with the ones in Syed's death scene and see he's the only English person with a hammock there. Furthermore, you can see him playing dice (or some game) with the other Chinese sailors in the sketch of the crew, indicating that they're close friends.
60. Samuel Peters. He never has a visible hammock while Nathan Peters number 48 does. That means he's the brother who died in the accident where Lars and Booth are present.

As you can see, every member of the crew is identifiable definitively by logic without any guess-work. It's easy to play the game and try to guess at parts, but this is how the game "wanted" you to solve each crew member's identity.

Most of the death scenes are straight-forward and only require recording who died. Sometimes you have the situation of not knowing who the person who does the killing actually is, but generally speaking the cause of deaths are easily determined.

But, some of them aren't. For these problem childs, so to speak, I've created an additional list.

There is some leeway in how you record the deaths, and who or what you attribute them to.

X. Any death that is committed by a mermaid with a spike, or a crab monster with a spike: There has been some confusion, especially among ESL players, about what exactly constitutes a 'speared' vs. a 'spiked' death. In general, if the thing doing the killing is long, singular, and thrown, it's a spear. If it's short, there are several of them, and it's more close-quarters, it's a spike. However, the game will generally accept either 'spiked' or 'speared' as a correct answer. Choosing 'spiked' will automatically pair it with 'by a beast'. If you choose 'spear' you must then choose 'beast'.

Thomas Sefton: He is specifically struck with a tail. Not spiked or speared.

Lau Hok-Seng: In assigning blame, you must choose the man in the firing squad whose bullet actually connects, which is Brennan's.

Nunzio Pasqua: You can't see what 2nd mate Nichols is using on him, but given it's too short to be a sword, and he isn't clubbing him, and he certainly isn't punching him, you can assume Nichols has a knife in his hand and is stabbing him. 'Knifed by'.

Zungi Sathi: This is perhaps the death that is most tricky, and it's really something you can easily get stuck on. You can clearly see Zungi get speared by the crab monster before he crawls away. However, he doesn't die from it. He huddles against the side of the ship until he's shot by a bullet that misses the crab monster, goes through the side of the ship, and just happens to penetrate him. If you look at the ship's wall right over his corpse, you can see the bullet hole in the ship's side (not in a memory, in the present). You furthermore have to look through the slat at just the right angle to find who actually fired the shot, and discover the blame falls on the Bosun's Mate.

George Shirley: This death is tricky because you don't actually see his dead body. He simply goes from trying to pull on Wolff in one scene to being completely missing from the next, even though he's listed as dying in that scene. So, what happened? He's not still on the boat. In the scene where Wolff is about to get shot by the cannon, you can see he's bracing himself against the window that leads outside. He either fell out from the force of the shot, or a tentacle pulled him over. "Fell overboard" works here, but so does "shot by a cannon" I believe.

John Naples: It's difficult because there's very little prelude to it, but you can see the sword on the floor and everyone is mad at Dahl, so Dahl used the sword on him.

Samuel Galligan: You have to pay attention to It-Beng Sia's movements in the scenes leading up to the death. It-Beng frees himself by sawing his binding ropes against the mermaid's spear, picks up the knife, and then kills him.

Bun-Lan Lim: It's requires seeing the scene before her 'death' technically, but it's easy to see she had her neck clawed by the mermaids. I think "eaten" may work too.

Alexei and Alarcus: They can be seen being pulled out of the boat into the water. "Drowned by a beast" works for both.

The "Unknowns" in the Doom chapter:

Duncan, Booth, and Nathan Peters: In Maba's death memory, you can look out into the ocean and see the kraken throwing their rowboat into the air and sending all three flying into the sea. It's safe to assume they all drowned and the game will accept that fate. They are definitely not alive.

Omid, Finley, Wei Lee: You can see Omid falling overboard from the rigging, and both Wei Lee and Finley being grabbed at various points in the Doom memories that are on the main deck. "Fell overboard," "drowned by the beast" or perhaps even "torn apart by the beast" all work for them.

Bosun's Mate: It's stated in the Bosun's death scene that his mate was torn apart by the beast. I think 'drowned' may also work.

Finally...

Captain Witterel: If you're going for the "Captain Did It" achievement, make sure you list his death as a gun suicide. Not "shot by Captain Witterel."