See his autobiography, Boyhood and Youth (1917); biographies by T. G. Strong (1917) and E. S. Martin (2 vol., 1920).
He was born at Salem, Massachusetts, the son of physician George Choate, the brother of George C. S. Choate, and nephew to Rufus Choate. After graduating from Harvard College in 1852 and Harvard Law School in 1854, he was admitted first to the Massachusetts (1855) and then (1856) to the New York bar, and entered the law office of Scudder & Carter in New York City.
His success in his profession was immediate, and in 1860 he became junior partner in the firm of Evarts, Southmayd & Choate, the senior partner in which was William M. Evarts. This firm and its successor, that of Evarts, Choate & Beaman, remained for many years among the leading law firms of New York and of the country, the activities of both being national rather than local.
During these busy years, Choate was associated with many of the most famous litigations in American legal history, including the Tilden, AT Stewart, and Stanford will cases, the Kansas prohibition cases, the Chinese exclusion cases, the Maynard election returns case, and the Income Tax Suit. In 1871 be became a member of the Committee of Seventy in New York City, which was instrumental in breaking up the Tweed Ring, and later assisted in the prosecution of the indicted officials. In the retrial of the General Fitz-John Porter case he obtained a reversal of the decision of the original court-martial.
His greatest reputation was won perhaps in cross-examination. In politics he allied himself with the Republican Party on its organization, being a frequent speaker in presidential campaigns, beginning with that of 1856. He never held political office, although he was a candidate for the Republican senatorial nomination against Senator Thomas C. Platt in 1897. In 1894 he was president of the New York state constitutional convention.
He was appointed, by President McKinley, U.S. Ambassador to the United Kingdom to succeed John Hay in 1899, and remained in this position until the spring of 1905. In England he won great personal popularity, and accomplished much in fostering the good relations of the two great English-speaking powers. He was one of the representatives of the United States at the second Peace Congress at the Hague in 1907.
Several of his notable public addresses have been published. The Choate Story Book (1903) contains a few of his addresses and after-dinner speeches, and is prefaced by a brief biographical sketch. His country house, Naumkeag, was designed by Stanford White and now open as a nonprofit museum in Stockbridge, Massachusetts.