Born to a family of vaudeville performers, Landis later travelled throughout the American West working at a variety of jobs. In 1937 he enlisted in the Mackenzie-Papineau Battalion of the International Brigade in Spain during the civil war, serving as a scout and artillery spotter. He served in the battles of Aragon and Teruel and before departing Spain was able load his unit's archives on the unit onto a ship that left the country.

In 1965 Landis wrote a fantasy novel A World Called Camelot. He later published sequels Camelot in Orbit (1978), The Magick of Camelot (1981), and Home to Avalon (1982).

In 1967 Landis published his non fiction book The Abraham Lincoln Brigade that was the result of many years of research and interviews with survivors of the Brigade.

Landis and Mandy Harriman, a fellow International Brigade veteran started Camelot Publishing, whose product included the magazines Coven 13 that printed a variety of fantasy and witchcraft stories including the two part story Let There Be Magick under the nom de plume of James R. Keaveny that was another name for A World Called Camelot. He also published Dealer's Voice a motorcycle magazine.

In 1972 he published Spain the Unfinished Revolution through Camelot publishing. He was awarded the Order of Friendship of Peoples by the Soviet Union.

Two years after his death, Death in the Olive Groves: American Volunteers in the Spanish Civil War 1936-1939 a re-edited and shorter version of his The Abraham Lincoln Brigade was published. Amazon.com: Death in the Olive Groves: American Volunteers in the Spanish Civil War 1936-1939: Arthur H. Landis: Books