It is well known that Alexander Hamilton joined the New York state militia while still attending college. However, many of the details given by Hamilton’s friends and biographers have been questioned and, indeed, many eyewitness statements appear contradictory. The following excerpt from Alexander Hamilton: The Formative Years firmly establishes when Hamilton joined the militia, which company he belonged to, and reveals some interesting newly discovered details about his militia service:

According to Nicholas Fish, “In the year 1775, immediately after the battle of Lexington,” news of which reached New York City on April 23, Hamilton “attached himself to one of the uniform Companies of Militia then forming for the defence of the Country by the patriotic young men of this city.” Less than two months later, on June 14, 1775, Hamilton appeared on a list as a private in the militia. Thus, sometime between April 23 and June 14, 1775—probably in late April or early May based on Fish’s account—Hamilton, along with Robert Troup and Nicholas Fish, enlisted in the militia. Robert Troup reported that the company he and Hamilton joined “was uniformed in short green coats and leather caps having the inscription of ‘Freedom or death’ in front.” Troup wrote that the company was commanded by a Major Fleming, but Hercules Mulligan and Nicholas Fish said it was commanded by Captain Fleming, whereas that list from June 1775 had him listed as Colonel Fleming. According to a list of New York’s “Independent Foot Companies” dated August 9, 1775, the Corsicans had “short Green Coats, Small round Hats Cock[ed] on one side. A Red Hart of Tin with the words, God and our Right, round the Crown Liberty or Death.” Edward Fleming was captain of the Corsicans and lieutenant colonel of the battalion. With the correct captain, nearly the same motto, and the same green coats, Hamilton clearly belonged to the Corsicans.

John C. Hamilton, however, said that Alexander Hamilton, Robert Troup, and Nicholas Fish were in a militia company called the Hearts of Oak. But the Hearts of Oak do not appear on the catalog of New York militia companies from August 9, 1775. On August 28, 1775, Edward Fleming was appointed Deputy Adjutant General for the New York Department. With this promotion, Fleming was no longer able to command the Corsicans. On a list of companies dated September 14, 1775, the Corsicans no longer show up but there appears out of nowhere the “Hearts Oak,” or “Hearts of Oak” as it was called in a subsequent list. John Berrian, who had been a lieutenant in the Corsicans, was captain of the Hearts of Oak. Frederick Jay, John Jay’s younger brother, who had been second lieutenant of the Corsicans, became first lieutenant of the Hearts of Oak. With two former Corsicans taking command of the Hearts of Oak and John C. Hamilton putting Hamilton, Fish, and Troup in the company, it is clear that the Corsicans sometime between August 9 and September 14 became the Hearts of Oak, either by changing its name or by the members of the old company forming a new one. Thus, Hamilton served first in the Corsicans and afterwards in the Hearts of Oak.

Alexander Hamilton dove right into his military training with characteristic enthusiasm and energy. Nicholas Fish remembered how Hamilton “devoted much time attending regularly the parades and performing tours of duty with promptitude and zeal.” Robert Troup recalled that “the Company met every morning, for a considerable time, for exercise in the Church Yard of St. George’s Chapel in New York,” and that Hamilton “was constant in his attendance and very ambitious of improvement. He became exceedingly expert in the manual exercise.” Within just weeks of enlisting, Alexander Hamilton had so impressed his superiors that he was recommended for promotion by being included in a June 1775 “List of Gentlemen who were deemed Qualified to Serve as Officers in the Provincial Army . . . if one should be raised.”