Peter Fenelon Collier (December 12, 1849 – April 23, 1909) was an Irish publisher, the founder of the publishing company P.F. Collier & Son, and in 1888 founded Collier's Weekly.
He was born in Myshall, County Carlow, Ireland, on December 12, 1849, to Robert Collier and Catherine Fenelon. He emigrated to Dayton, Ohio, United States, in 1866 when he was seventeen years old. He attended St. Mary's Seminary in Cincinnati for four years. He then worked for Sadler and Company, a publisher of schoolbooks. With $300 that he saved as a salesman, he bought the printing plates to Father Burke's Lectures. In a single year, his sales were $90,000. In July 1873 he married Catherine Dunne.
In 1874, he published a biography of Pius IX and later published Chandler's Encyclopedia and Chamber's Encyclopedia. He then began publishing "Collier's Library", a series of popular novels.
He later formed his own publishing company printing books for the Roman Catholic market. He founded Collier's Once a Week in April 1888. It was advertised as a magazine of "fiction, fact, sensation, wit, humor, news". By 1892, Collier's Once a Week had a circulation of over 250,000, and was one of the largest selling magazines in the United States. In 1895, the name was changed to Collier's Weekly: An Illustrated Journal.
Collier died on April 23, 1909. His will left most of his estate to his wife and son. His estate included shares in the Rumson Polo Club, Monmouth Agricultural Fair Association, Was co-owner of Colliers Weekly, shares in the Meadow Yacht Club, shares in Kentucky Horse Show Company, Tammany Publishing Company and a life insurance policy. All his assets were liquidated and amounted to $2,890,440 (approximately $77,046,000 today). His wife received a life estate and an annuity of $33,044. His son received $2,280,410 and the rest was distributed to various organizations.