Arkham (born in 1890) is the only son of mentally-ill Elizabeth Arkham, Amadeus watched his mother struggle with her illness for years, which drove him to become a psychiatrist. Years later, having earned a residency at the Metropolis State Psychiatric Hospital, he returned home, and having found his mother to be growing worse, aided her in committing suicide. After her death, he became the sole owner of her home, the Mercey Mansion, which he decided to turn into a facility for the mentally ill. He gave up his practice at MSPH and moved his wife, Constance Arkham, and daughter, Harriet, into the mansion.
During the remodeling process, one of Arkham's former patients, Martin "Mad Dog" Hawkins, escaped from Metropolis Penitentiary and broke into the Arkham family living quarters. Amadeus returned home that night and discovered both his wife and daughter had been raped and murdered, with Hawkins' nickname carved into Constance's chest. When the Asylum opened that November, Hawkins was captured and became one of its first inmates. Amadeus insisted on treating him personally. After six months of treatment, Amadeus could see no improvement in Hawkins and killed him with a lethal dosage of electroshock therapy. The incident was ruled accidental but was only the beginning of Amadeus' slide into insanity, and eventually, he ended up dying as an inmate in his own asylum in 1963.
- Medicine: Doctor Arkham was formally trained as a pharmaceutical doctor prior to creating Arkham Asylum.
- Psychiatry: Doctor Arkham has been training in the field of psychiatry for years prior to it becoming an actual science, he later studied and was given degrees for his work.
- Mental Illness: Doctor Arkham has slowly degraded over time, losing his grip with sanity and eventually dying as an inmate in his own asylum.
- 5 Appearances of Amadeus Arkham (New Earth)
- 2 Images featuring Amadeus Arkham (New Earth)
- Quotations by or about Amadeus Arkham (New Earth)
- Character Gallery: Amadeus Arkham (New Earth)