- "Humanity has won its battle. Liberty now has a country."
- — Marquis de Lafayette
The Marquis de Lafayette is first seen in the beginning of Act One, where he, along with John Laurens and Hercules Mulligan, question Aaron Burr's intentions, and ask him why he is stalling when the Revolution was around the corner. Lafayette is also first introduced to 19-year-old Alexander Hamilton, a new immigrant from the Caribbean ("Aaron Burr, Sir"). He and Hamilton soon become close friends and Revolutionary allies, along with Laurens and Mulligan, and they sing of effort they will put into rising up in the new country ("My Shot"). They then sing in the spirit of the Revolution together ("The Story of Tonight").
Alexander gets married to Elizabeth Schuyler, and Lafayette, Laurens and Mulligan congratulate him. Aaron Burr visits them to congratulate them on their success; they ask about his lover, to which he replies that he can't see due to her husband being a British officer ("The Story of Tonight (Reprise)").
Lafayette then returns to the colonies and is formally introduced, in which he begins his important role in victories during the Revolution. Lafayette also persuades a reluctant George Washington to allow Hamilton to join to army once more, as he believed Hamilton was their key to success ("Guns And Ships"). Then, at the Battle of Yorktown, Hamilton and Lafayette unite to lead the American forces against the British, and Hamilton promises to aid Lafayette in the French Revolution to repay what Lafayette was doing for the American Colonies ("Yorktown (The World Turned Upside Down)").
Following the Battle of Yorktown, Lafayette returns home to France to his own country's revolution, and as such makes no appearance in Act Two. He is mentioned in one of Hamilton and Jefferson's debates (Cabinet Battle #2), when Jefferson, angered by Hamilton's refusal to send funds, asks if Hamilton has forgotten his friend. Hamilton snaps back that Lafayette was his friend before he was Jefferson's, and states that as Lafayette is a smart man, Hamilton is not worried about him.
- Daveed Diggs originated the role until July 15, 2016.
- Seth Stewart played the role from July 18, 2016 to July 23, 2016.
- Andrew Chappelle took over from July 25, 2016 to July 30, 2016.
- James Monroe Iglehart took over the role starting April 18, 2017.
- Gilbert du Motier, Marquis de Lafayette, was not a member of the Sons of Liberty nor did he join up with the political revolutionaries as portrayed in the show. Going against his family's and King Louis XVI's wishes, the Marquis arrived in the New World at the age of 19 to join the American Revolution. Upon his arrival, the Marquis caught the attention of General George Washington who quickly made the Marquis a member of his staff around the same time as Hamilton. This is where Alexander Hamilton and the Marquis developed their friendship and began their famous written correspondence.
- The Marquis de Lafayette returned to France to great fanfare following the victory against the British where he joined the French abolitionist movement while working as a diplomat between France and the United States. On July 11, 1789, the Marquis presented "the Declaration of the Rights of Man and of the Citizen" to the National Assemby, a French variation on the Declaration of Independence written with the help of his buddy Thomas Jefferson. Several events during the revolution led to the Marquis being branded as a loyalist, which began his decline in the eyes of the French people.
- Lafayette, at the invitation of then President James Monroe, traveled to the US for a Grand Tour in celebration of the 50th year of American Independence. He spent nearly a year traveling the nation, being honored every step of the way. By the time he left, John Quincy Adams was President.
- Lafayette arrived in America when he was nineteen years old. At the end of the war, he was twenty-six.