William Astor Chanler (June 11, 1867 – March 4, 1934) was a U.S. Representative from New York, son of John Winthrop Chanler and Margaret Astor Ward. He was the great-grandson of William Backhouse Astor, Sr.. He was married to actress Beatrice Minerva Ashley and they had two sons William Astor Chanler Jr. and Sidney Ashley Chanler. William Astor Chanler Jr. was an attorney and published historian. Sidney Ashley Chanler was a public relations executive.

Born in Newport, Rhode Island, Chanler attended St. John's School, Ossining, New York, Phillips Academy, Exeter, New Hampshire, and Harvard University for two years. A Fellow of the Royal Geographic Society of London, in 1889 William Chanler explored the territory in the vicinity of Mount Kenya with Austrian Ludwig von Hohnel. Many of the African animals in the American Museum of Natural History were donated by him after being collected on this expedition.

He was as delegate to the State Republican convention at Saratoga, New York in 1896 and served as member of the State assembly in 1897. During the Spanish-American War, he was appointed captain and assistant adjutant general of Volunteers on May 10, 1898. He served as acting ordnance officer, Cavalry Division, Fifth Army Corps, from May 23 to August 23, 1898. He participated in the Battle of Santiago de Cuba.

Chanler was elected as a Democrat to the Fifty-sixth Congress, serving from March 4, 1899 to March 3, 1901. He was not a candidate for renomination in 1900.
Traveler, author, and explorer.
He had spent considerable time in Europe and moved there in 1920.
He died in Menton, Alpes-Maritimes, France on March 4, 1934. His remains were returned home for interment in the Trinity Church Cemetery in New York City.

An owner of Thoroughbred racehorses, he raced both in the United States and in France. One of his trainers was U.S. Racing Hall of Fame inductee, Preston M. Burch.

First hand account recorded on August 17, 1905;

"Late this evening I went up to the Manhattan Casino. The William Astor Chanler association was holding its summer night festival and outing there. Mr. C. has explored a little in Africa: he is now exploring darkest Tammany. I noticed him, a manly young fellow, surrounded by some politicians, and while apparently a good mixer, he betrayed a subconscious pant as if the element was not just to his taste. So have I felt and bravely overcome. So I permitted the bands, that played unusually sweet music, to set me whirling almost any petticoated reveler that came to hand in the mazy dance. So I lived awhile, while others paused."

Edwin Manners