Sir Sandford Arnot Fleming was born on January 7, 1827, in Kirkcaldy, Fife County, Scotland.

He was a Canadian civil engineer, scientist, and surveyor. He studied surveying in his hometown before immigrating to Canada in 1845. He began accumulating railway experience during the 1850s and 1860s when he served as Chief Engineer of various railways in Upper Canada and Nova Scotia. He also designed Canada's first postage stamp, the three-penny beaver, issued in 1851. In 1867, he was appointed Chief Engineer of the Inter-Colonial Railway, which was to link Nova Scotia to central Canada as part of the Confederation Pact. In 1871, he was made Chief Engineer of the Canadian Pacific Railway, in charge of supervising the construction of the railway that would extend from the Atlantic to the Pacific. Fleming led a gruelling cross-country survey expedition to pick a route for the railway. This surveying mission across Canada gave him the idea for a standard system of time zones. He proposed the system we use today, which was adopted in 1884, and he is known for this as the "Father of Standard Time." In 1880, he took the position of Chancellor of Queen's University in Kingston, Ontario and held it for 35 years. He played a pivotal role in increasing the importance of science at Queen's. He was vice president of the Ottawa Horticultural Society and in 1888, he became the first president of the Rideau Curling Club. In 1897, he was knighted by Queen Victoria. Fleming was designated a National Historic Person in 1950, on the advice of the National Historic Sites and Monuments Board.

In 1855, he married Ann Jane "Jeannie" Hall (1831–1888). He died on July 22, 1915, in Halifax, Nova Scotia.