While on vacation from performing in his hit Broadway show In the Heights, Lin-Manuel Miranda read a copy of the 2004 biography Alexander Hamilton by Ron Chernow. After finishing the first few chapters, Miranda began to envision the life of Hamilton as a musical, and researched whether a stage musical of Hamilton's life had been created: all he found was that a play of Hamilton's story had been done on Broadway in 1917, starring George Arliss as Alexander Hamilton.
Miranda began a project titled The Hamilton Mixtape. On May 12, 2009, Miranda was invited to perform music from In the Heights at the White House Evening of Poetry, Music and the Spoken Word. Instead, he performed the first song from The Hamilton Mixtape, an early version of what would later become "Alexander Hamilton", Hamilton's opening number. He spent a year after that working on "My Shot", another early number from the show.
Although Miranda took some dramatic license in recounting the events of Hamilton's life, both the story and the lyrics in the musical numbers were heavily researched. Many of the songs included in the show contain lines lifted directly from primary source documents including personal letters and other documents such as The Federalist Papers and the infamous Reynolds Pamphlet.
Miranda performed in a workshop production of the show, then titled The Hamilton Mixtape, at the Vassar College and New York Stage and Film Powerhouse Theater on July 27, 2013. The workshop production was directed by Thomas Kail and musically directed by Alex Lacamoire. The workshop consisted of the entirety of the first act of the show and three songs from the second act. The workshop was accompanied by Lacamoire on the piano.
Of the Vassar workshop cast, only three principal cast members played in the Off-Broadway production: Miranda, Daveed Diggs, and Christopher Jackson. Utkarsh Ambudkar, who played Aaron Burr at Vassar later stated that while the part was written with him in mind, his lack of sobriety at the time led to him being replaced. The original Off-Broadway cast moved to Broadway, except for Brian d'Arcy James, who was replaced by Jonathan Groff as King George III.
In 2014, there was a workshop production at the 52nd Street Project starring Miranda as Hamilton, Leslie Odom Jr. as Burr, Diggs as Lafayette/Jefferson, Phillipa Soo as Eliza, Renée Elise Goldsberry as Angelica, Anthony Ramos as Laurens/Philip, Okieriete Onaodowan as Mulligan/Madison, Ciara Renée as Peggy/Maria, James as King George III, and Isaiah Johnson as Washington. An audio recording of this production is available on YouTube.