Born in Leeds, England, on May 10, 1922, John Rowe Townsend grew up a poor child in a large industrial city. His playground was the city street, and his amusements were adventure books. His father suffered from Parkinson's disease and could not work, so the family's income was limited. Thus it was fortunate that Townsend won a scholarship to Leeds Grammar School, although his presence there caused him many anxieties. Most of the other students had plenty of money, and field trips and uniforms were expensive. Townsend avoided forming close friendships so he would not be expected to pay his way to events with other boys; he also skipped school trips because of the expense.

In Townsend's family, a good education was respected but not necessarily desired, and he left school at age sixteen to go to work. During World War II, he served in the Royal Air Force, although not as a pilot. While stationed for many months in Florence, Italy, a city full of artistic treasures and steeped in history, Townsend learned to appreciate art. After the war he took a trip to Cambridge, England, and stopped in at the university to express an interest in becoming a student. Perhaps because he was a veteran, he was admitted, even though many other applicants had attended better preparatory schools and had applied to the university properly. Townsend studied English literature and became interested in journalism. He edited the university newspaper and later got a job on the Manchester Guardian.

Townsend had always wanted to be a writer; in fact, he wrote a novel when he was eight years old. But it was not until he became the children's book editor for the Guardian, thirty years later, that he thought of writing a novel for young adults. His childhood experiences with poverty and his work on an article about the National Society for the Prevention of Cruelty to Children, which showed him how desperately poor and neglected some children could be, provided him with ideas for Trouble in the Jungle. He continued working as a journalist for many years, writing novels on the side until he could make enough money from his fiction to support his family.

Townsend married shortly after World War II, and he and his wife, Vera, had three children, one of whom now lives in Leeds. Vera died in 1973. Townsend now lives in Cambridge in a house he owns jointly with Jill Paton Walsh, another author of young adult novels. They both spend part of each year as visiting lecturers at the Center for Children's Literature at Simmons College, Boston. In addition to writing novels, Townsend writes books and articles about children's literature.

His books have won several awards. In 1963 he was the runner-up for the Carnegie Medal for Hell's Edge, and The Intruder won the International P.E.N. Silver Pen Award and the Boston Globe- Horn Book Award. He has been named to the Horn Book Honor List, and many of his novels have been chosen as American Library Association Notable Books.