Allan McLane Hamilton FRSE (October 6, 1848 – November 23, 1919) was an American psychiatrist, specializing in suicide and the impact of accidents and trauma upon mental health, and in criminal insanity, appearing at several trials.

[6] As a boy and later on, Hamilton ate Christmas dinners at the old-fashioned English home of David Colden (1733–1784), a son of Lt. Gov.

[7] As a young teenager during the American Civil War, Hamilton took part from 1861 until 1863 in "repeated drillings, and marchings in the Rochester Home Guards, a sort of Boy Scout organisation.

[8][9] Louis was killed while leading his command during Custer's 1868 attack on Black Kettle's Cheyenne encampment in the Battle of Washita River.

[10] Specializing in "nervous diseases", Hamilton was one of the first medical practitioners in America to use electricity for cauterization; his text on Clinical Electro-Therapeutics was published in 1873.

[11] During his early years of practice, he was the doctor to much of the old New York society that lived about Washington Square, lower Fifth Avenue and St. John's Park.

After the Civil War, however, Hamilton was witness to their gradual decline and thinning out, as they were overtaken in the forefront of society by so-called "new money" people who had earned their wealth, for example, in the Comstock Lode.

[7] In the 1870s, Hamilton served as a member of the Coroner's jury in New York; in an 1874 inquest, he agreed with William A. Hammond that hydrophobia was a disease of the nerve centers and not a blood poison.

[13] In this paper, he argued that suicides were more strongly felt in metropolitan areas due to the use of intoxicating drinks or narcotics, nervous disease, seduction, immoral habits, and disappointment.

[22][23] In 1911, he published an op-ed article in The New York Times protesting Gertrude Atherton's characterization of his grandfather in her novel, The Conqueror, as someone "whose life was dotted with questionable affairs and escapades with women.

He became close there with Lord John Norton, with writers Norman Douglas, Marion Crawford, and Maxim Gorky, and with the painter George Bernard Butler (who had served with Hamilton's brother in the Civil War).

[31] Allan McLane Hamilton died on November 23, 1919, at his summer residence, Fair Meadows, in Great Barrington, Massachusetts, aged 71.