Tom Forrestall was born in the Annapolis Valley of Nova Scotia on March 11th, 1936. He grew up in Middleton and Dartmouth and began to attend art classes at the Nova Scotia Collage in Halifax at an early age.

In 1954 Forrestall was awarded an entrance scholarship to the Fine Arts Faculty at Mount Allison University from which he graduated in 1958. In the same year he received a Canada Council Grant for independent study (one of the first granted) and traveled throughout Europe. In 1959 he became the assistant curator of the Beaverbrook Art Gallery in Fredericton, New Brunswick, and in 1960 received his first major commission – a painting to be presented to Princess Margaret as a wedding gift from the Province of New Brunswick. Shortly thereafter, Forrestall, having supporting himself in various related jobs, began to devote himself to full time painting.