September 25, 1816, Manchester, Lancashire, England.
March 25, 1890, Fall River, Massachusetts.
Oak Grove Cemetery, Fall River, Massachusetts.
John was the son of Robert Westall and Mary Walker. He married twice, to Sophronia Wight and Julia Wight.
Westall emigrated to America around 1830, and lived with his father in Lowell, Massachusetts. Around 1837, he moved to Providence, Rhode Island, and in 1838, to Fall River, Massachusetts. He worked in Fall River for 36 years as a designer at the American Print Works, studying theology in his spare time. Though he had planned to become an Episcopal minister, he was influenced by the works of Emmanuel Swedenborg, and he joined the Church of New Jerusalem instead. He was a lay reader and service leader for many years, but declined a number of requests to become a full time minister.
During this period, Westall visited France, England, Switzerland, Italy, Egypt, the Holy Land, Turkey, and Greece. These travels and experiences provided background for essays, poems, and other literary efforts. For a while, he served as a newspaper editor in Fall River.
In 1877, Westall became a full time Swedenborgian pastor, and was very active in state and regional affairs. He served as a delegate to political conventions, as a member of the school committee, a library trustee, and in other positions. He also enjoyed playing the violin and composing music. In 1880, Brown University gave him an honorary degree. The Westall School in Fall River, Massachusetts, is named after him.