While not much is known about the early life of Edward Mallen, he is remembered as an artist and frequenter of Pfaff's. William Winter identifies "Edward F. Mullen" as one of the artists who frequented Pfaff’s Cave along with Launt Thompson, George Boughton, and Sol Eytinge, Jr. (Old Friends 66, 88). Walt Whitman, a close friend of his, is also quoted as saying that "Mullin" was "among the leaders" at Pfaff’s (Bohan 134; T. Donaldson 208-209).
Born in County Cork and raised primarily in Limerick, Ireland, Fitz-James O'Brien moved to New York City in 1852. Descending from an Anglo-Irish landholding family, O'Brien received his inheritance (estimated at £8000) at about the age of 21. Between 1849 and 1851, it is believed that O'Brien edited a failed literary magazine called The Parlour Magazine of the Literature of All Nations and squandered his inheritance (Wolle 21). Leaving England almost penniless, O'Brien immigrated to America and made the U.S.