Parkinson, James Joseph (‘J. J.’) (c.1870–1948), racehorse trainer and senator, was born near Tramore, Co. Waterford. After qualifying with first-class honours in London as a veterinary surgeon, he returned to Ireland and was apprenticed to one of the leading trainers in Irish racing, Michael Dennehy, who was based at French House on the Curragh in Co. Kildare. Parkinson soon established himself as a trainer in his own right at Maddenstown Lodge on the Curragh and his success over the following decades was remarkable. During the years 1905–6 he trained the horses of Boss Croker (qv) and the partnership was hugely successful, until dissolved by J. J. because of Croker's extravagant ambitions and arrogant manner. In the meantime, J. J.'s victories included six Irish classics, including four Irish Oaks and the Irish Derbies of 1917 and 1919. He also saddled four winners at Epsom on Derby day in 1909; a fifth horse was beaten by a short head, having jumped the road on the way to the finish line.
Parkinson's career total as a trainer was 2,577. He led the list eight times for the most prize-money won in a season and in 21 of the 32 seasons from 1906 to 1937 trained more winners than any other Irish trainer. He is also the only owner (as distinct from trainer) in Irish racing history to date to win over 1,000 races. Perhaps his most noteworthy year was 1914 when he secured a remarkable treble, winning the title of leading trainer, having more winners than any other owner in the country, and his son Billy becoming champion jockey. Before that year Billy, who was just 18, had never ridden racehorses and had no interest in the sport. Billy went on to have a fine career, riding 72 winners in 1915 (which remains the amateur record for the highest number of races won in a single year), before dying at the age of 46.
As well as being the leading trainer in the country, J. J. Parkinson was the foremost breeder and exporter of horses in Ireland, and revolutionised the trade. He established breeding operations on opposite sides of the Curragh in Kildare, named the 1st Flyer Stud and Pollardstown Stud, and exported horses to countries around the world including South Africa, Malaya, and India; his last major order was to Norway when racing resumed there after the second world war. He served as a director of Tramore and Limerick racecourses, and was also a director of the Tote and of Goffs. Other business interests included Wolfhill Colleries in Athy, Co. Kildare, which nearly bankrupted him, and a timber processing firm at Moore Abbey in Kildare, which was successful particularly during the war when imported timber was scarce. He was nominated to the first seanad by W. T. Cosgrave (qv) in 1922 and remained a member until its abolition in 1936; he served as a member of the seanad established under the 1937 constitution until he retired owing to ill health in August 1947, being elected on each occasion on the cultural and educational panel. He died 18 September 1948 and, after requiem mass at St. Brigid's church in Suncroft, Co. Kildare, was buried in Tramore. A huge crowd attended his funeral, including the minister for justice, Seán Mac Eoin (qv), and leading representatives from the worlds of politics, business, and racing.
Parkinson married Margaret Brophy from Naas, Co Kildare, and they had three sons and five daughters. His stable was taken over by his third son, Emmanuel. J. J.'s record for a trainer of 134 winners in a season was only beaten by Jim Bolger in 1990 and his career total of winners was only beaten by Dermot Weld in August 2000. His record of wins as leading trainer for 21 years remains unbeaten.