Fairbanks was born Douglas Elton Thomas Ullman (spelled "Ulman" by Douglas Fairbanks Jr. in his memoirs) in Denver, Colorado, the son of Hezekiah Charles Ullman (September 15, 1833- February 23, 1915) and Ella Adelaide (née Marsh; 1847-1915). He had two half-brothers, John Fairbanks, Jr. (born 1873) and Norris Wilcox (February 20, 1876 - October 21, 1946), and a full brother, Robert Payne Ullman (March 13, 1882 – February 22, 1948). His father was born in Berrysburg, Pennsylvania, but raised in Williamsport. He was the fourth child in a Jewish family consisting of six sons and four daughters. Charles's parents, Lazarus Ullman and Lydia Abrahams, had immigrated to the U.S. in 1830 from Baden, Germany.