[4][5] Founded in 1862[1] as the Manhattan Dispensary,[6][7] it served as a temporary American Civil War tent facility for returning Union Army invalidsDated/offense?.

The hospital assumed the city's largest ambulance district for many decades[1] and worked at the forefront of treatments for polio, alcoholism, and gynecological care.

[4] The Knickerbocker, similar to the television portrayal, had a standing policy of often refusing to treat African-American patients despite the hospital's mission to serve those who could not afford to pay for medical care.

[14] In the television series, Clive Owen's character, Dr. John Thackery, is based in part on Dr. William Stewart Halsted.

Dr. Halsted, a well-known physician who invented many new surgical instruments and techniques in the early 20th century, was, according to the Johns Hopkins Institute, known to be addicted to cocaine and morphine, like Thackery.