Given that Lin-Manuel Miranda wrote this musical based on the research of the life of a historical figure, there's no surprise there's a lot of hidden facts in the lyrics.
- During Thomas Jefferson's first number "What'd I Miss?" he tells a slave called Sally to "Be a lamb, darlin', won't you open" a letter. Research and DNA evidence had proved that Jefferson almost certainly had a long term affair with one of his slaves, Sally Hemings—who, incidentally, was the half-sister of his late wife—and fathered at least some of her children; hence the terms of endearment here. (In live performances, Hemings is briefly represented by a woman from the chorus who does a little shimmy for Jefferson as she opens the letter.)
- During "I Know Him", King George III alludes to the fact that Washington (6'2") was one of the tallest presidentsnote ("Next to Washington they all look small") and Adams (5'7") was one of the shortest ("That's that little guy who spoke to me").
- During "You'll Be Back", King George sings "When you're gone, I'll go mad." Which actually did happen; George III did indeed develop symptoms of insanity in the later years of his life.
- In "Meet Me Inside", Hamilton's comment of "John [Laurens] should have shot him [Lee] in the mouth, that would have shut him up" is a reference to the fate of Thomas Conway (also mentioned in the song), who had conspired against Washington and was shot in the mouth in a resulting duel over Washington's honor.
- Angelica in "The Schuyler Sisters" mentions that she wants to tell Thomas Jefferson to include women in the sequel to the Declaration of Independence. Angelica later in life developed a "lasting friendship" with Jefferson and Lafayette. It may also be a reference to the Seneca Falls Convention, which produced a document explaining feminist theory modelled after the Declaration. Reportedly, Jefferson originally had a line along the lines of "tell Angelica I said what's up" to further reference this real life relationship, but the line was cut.
- In "Helpless", Angelica teases Eliza that if the latter loved her then they would share Hamilton. Angelica in a real-life letter said something similar (see One True Threesome below), though given that she had already eloped with another man at this point it's generally considered to have just been a joke. Similarly, her later comments about Hamilton's writing implying he has feelings for her actually did occur in one of their exchanges, but with reversed roles.
- Going off of this point, Angelica's explicitly romantic feelings for Hamilton may be an invention for the show, but they're not pulled from thin air; Angelica and Hamilton had so much chemistry that many people at the time thought they were lovers, and in modern times the idea that the two of them had an affair has not been completely discounted.
- Although Washington's 32-page farewell address was largely condensed and paraphrased, it is true that, while all of the ideas expressed in the letter were Washington's, Hamilton wrote most of it.
- "The Reynolds Pamphlet" makes it very clear that Miranda read the document before writing the number - of the four lines that are quoted from the document In-Universe, 2.5 of them are lifted verbatim from the real pamphletSpecifically.
- In the first cabinet battle, Jefferson dares Hamilton to try taxing whiskey and see what happens next. Any historian can tell you what did happen when whiskey was taxed: a full fledged rebellion, which Washington and Hamilton proceeded to put down with extreme prejudice.
- All the comments from Eliza and Angelica about Hamilton's eyes make more sense with a little research - by most accounts on his physical appearance, Hamilton rather famously had purple eyes.
- In "The Election of 1800", it's noted that Burr is popular with women, even telling a group "Ladies, tell your husbands, vote for Burr". It's played in-universe as Burr being a Chick Magnet, but in real life Burr was incredibly progressive for his time, occasionally advocating for women's rights to vote.
- In the same song, Jefferson says of John Adams "I love the guy but he's in traction". In real life, Jefferson and Adams became close friends during the Revolution. They worked together on the Declaration of Independence, and after the war, they were both assigned to diplomatic positions in Europe— Adams was in London and Jefferson in Paris, so they were going through a lot of the same problems at the same time and were fire-forged friends, with Adams specifically remembering the time he formally introduced Jefferson to King George III and the two of them were openly snubbed. As seen in the show, Jefferson went on to absolutely crater Adams' political career (in particular, Abigail Adams accused him of directly and personally campaigning for the presidency, which was seen as crass before Jefferson and Burr made it cool) and Adams managed to both passive-aggressively snub him and set the precedent for peaceful transfer of power after an election loss by skipping town in the dead of night. However, they did make an effort to bury the hatchet in the twilight of their lives (Adams saying they ought not to die without explaining themselves to each other) and kept up a lively correspondence that they knew would be studied by future historians - in fact, Adams' last words were "Thomas Jefferson lives", though he was unaware that Jefferson himself had died only a few hours earlier.
- At the time of the Revolution, it was considered improper for single women to introduce themselves to an eligible man, and they had to wait for a man or a woman who was already married to make the introduction for them. Thus, Angelica flaunts convention by taking it upon herself to introduce Hamilton to Eliza, while making sure she stays respectable.note
- The show's final duel between Hamilton and Burr is full of details that show just how much research was put into it:
- In "The World Was Wide Enough", Burr has a line, "Somebody tells me, 'You'd better hide'". Think this is just because of Hamilton being popular? No. Since Hamilton was aiming at the sky during their duel, Burr would be charged with murder, not just duelling.
- At the final duel, Burr proclaims, "They won't teach you this in your classes, but look it up: Hamilton was wearing his glasses." Though you may indeed not have learned this at school, it is indeed true.
- While Burr was historically unashamed of killing Hamilton in the duel, he really was quoted as saying "I should have known the world was wide enough for Hamilton and me" later on in his life.
- At one point, Burr mentions that Hamilton "fiddled with the trigger" of his gun. In real life, part of the reason why Hamilton's intentions during the duel are so murky is that he had a secret hair trigger installed on his gun for the duel, but after the duel it was discovered to have been deactivated; some say the trigger is evidence that he secretly wanted to kill Burr, while others say that it's deactivation implies that he had no such intention.
