Agnes Boulton was a successful "pulp fiction" writer in the 1910s, later the second wife of Eugene O'Neill. Prior to their marriage, she wrote for such magazines as Breezy Stories, Snappy Stories, and Young's Magazine. Boulton was born in 1892 in England, the daughter of Cecil and Edward W. Boulton (an artist), but grew up in Philadelphia and later in West Point Pleasant, New Jersey.

Boulton met O'Neill in the Golden Swan Saloon, better known as The Hell Hole, in Greenwich Village. They married some six months later in Provincetown, Massachusetts. O'Neill, at the time, was considered a very promising author of one-act plays. During the first year of their marriage, he wrote Beyond the Horizon, his first full-length, Broadway play, which won the Pulitzer Prize in 1920. During the early years of the marriage, Boulton modified her writing and had two stories published by The Smart Set, an important magazine co-edited by H. L. Mencken and George Jean Nathan.

She gave birth to Shane O'Neill in 1919 and Oona O'Neill in 1925. The marriage came to an end when O'Neill left Boulton for the actress Carlotta Monterey in 1928.

Boulton published a novel, The Road Is Before Us, in 1944, and a memoir of the first year and a half of her marriage to O'Neill in 1958. Entitled Part of a Long Story, the memoir gives a fascinating portrayal of an odd literary marriage at its inception.

Contrary to the terms of the 1929 divorce settlement, Boulton had saved most of her letters to and from O'Neill, as well as some O'Neill manuscripts and other documents. The correspondence was published in 2000 by Fairleigh Dickinson University Press in a volume called A Wind Is Rising.

Boulton died in November 1968.

A further note: Oona O'Neill, Agnes Boulton's daughter, became Lady Oona Chaplin, wife of Charlie Chaplin.

Information provided by "Princess Kim"

Her second husband was Morris Kaufman.