M'nagalah is a shapeless alien life form from an unknown world. He is the self-proclaimed father of life on not only this Earth dimension, but many parallel worlds. He is considered the face and fountain of all human knowledge. He is the Cancer God. Manifesting on Earth some 200,000 years ago, he chose which life forms would prosper and survive their own evolution and which ones would serve only as food. As humanity began to grow, M'nagalah used his telepathic abilities to inspire the imagination of select individuals. In 1827, M'nagalah used his powers to inspire Edgar Allen Poe. In 1866, he reached out to inspire the creative energy of writer Ambrose Bierce. In 1896, M'nagalah's essence touched the mind of a six-year-old boy from Providence, Rhode Island named Howard Phillips Lovecraft. Lovecraft would grow up to become one of the most acclaimed writers of horror fiction of the 20th century.

Years later, a man named Abraham Monroe from the Pennsylvania mining town of Perdition used a spell book to evoke the essence of M'nagalah. Since that time, M'nagalah kept the community locked in a grip of evil. He began nesting in an old mine shaft called Tunnel 13 and over the span of generations continued to grow in both size and influence. In January 1974, the plant elemental known as the Swamp Thing came to Perdition. Jason Monroe, the great-grandson of Abraham Monroe was a slave to M'nagalah's whims and lured the Swamp Thing to Tunnel 13 so that M'nagalah could take control of him. By absorbing the Swamp Thing's mass, M'nagalah would have acquired enough raw power to dominate all of mankind. The Swamp Thing resisted M'nagalah's power and caused a section of the mine to collapse, trapping M'nagalah beneath a ton of debris.

Years passed, and M'nagalah continued to live and slowly regain his power. He became aware of an ideological war brewing between factions of chaos and order; faith and reason. M'nagalah somehow freed himself from Tunnel 13 and took up residence in the sewer systems beneath the city of Ivy Town. As Lord of Cancer, he began spreading his infection across the town's inhabitants in preparation for a battle with an alien race known as the Waiting. This brought him into contact with Ryan Choi, a twenty-six year old physics professor who had only recently assumed the mantle of the Atom. M'nagalah was in awe of Ryan's ability to alter his atomic size and tried to absorb him into his being. The Atom resisted M'nagalah' thrall, but there was another who did not - Giganta. Infected by M'nagalah' cancer, Giganta fought with the Atom and temporarily caused him great discomfort by swallowing him. After this battle, M'nagalah rose from his subterranean domain and manifested himself in Ivy Town.