Though he did not begin competitive rowing until the age of 25, John O'Neill, was already an adept paddler; growing up on the eastern coast of Nova Scotia, O'Neill had to row across Ketch Harbour in order to run errands for his father as a young boy. It was here that one of the greatest scullers of the first decade of the 20th century got his start. As a young man, O'Neill served with the Canadian Special Service Force during the Second Boer War. Upon his return to Canada, he joined the St. Mary's rowing Club in Halifax just 'for fun'.  Within two years, he had established himself as the best of the local scullers, winning the championship of Halifax Harbour in 1904. Following several more victories around the Maritimes, his club sent him to compete in the Middle States Regatta at Philadelphia in 1905. O'Neill did not disappoint, and claimed the singles title. He repeated the feat in 1907 when the event was held in Springfield, Massachusetts, and continued to shine in 1908 with a victory in the U.S. Association Singles event. O'Neill's crowning achievement came in 1909 at the U.S. National Regatta on the Detroit River. In an extremely close race with New York’s Dorando Miller, O'Neill managed to pull ahead to cross the finish line, claiming the North American single scull title. Records are scarce, but O'Neill is believed to be the first Canadian to win this championship. Upon his return to Halifax, the 32-year-old sculling champion received a hero's welcome; he was pulled through the streets in a carriage and praised in a public address by the mayor. O'Neill retired from competition shortly thereafter but continued to row throughout the rest of his life. Even at the age of 89, he was reported to be a regular on the waters around Halifax harbour.