William Sora Middlebro was a lawyer and political figure in Ontario

Ontario

Ontario is a province of Canada, located in east-central Canada. It is Canada's most populous province and second largest in total area. It is home to the nation's most populous city, Toronto, and the nation's capital, Ottawa....

, Canada. He represented Grey North

Grey North

Grey North was a federal electoral district represented in the Canadian House of Commons from 1867 to 1968. It was located in the province of Ontario. It was created by the British North America Act of 1867, which divided the County of Grey into two ridings: Grey South and Grey North...

 in the Canadian House of Commons

Canadian House of Commons

The House of Commons of Canada is a component of the Parliament of Canada, along with the Sovereign and the Senate. The House of Commons is a democratically elected body, consisting of 308 members known as Members of Parliament...

 from 1908 to 1917 as a Liberal

Liberal Party of Canada

The Liberal Party of Canada , colloquially known as the Grits, is the oldest federally registered party in Canada. In the conventional political spectrum, the party sits between the centre and the centre-left. Historically the Liberal Party has positioned itself to the left of the Conservative...

 and then from 1917 to 1921 as a Unionist Party

Unionist Party (Canada)

The Unionist Party was formed in 1917 by Members of Parliament in Canada who supported the "Union government" formed by Sir Robert Borden during the First World War....

 member.

He was born in Orangeville, Ontario

Orangeville, Ontario

Orangeville is a town in south-central Ontario, Canada, and the seat of Dufferin County.-History:Before European settlers, Orangeville was thought to be a native hunting ground...

, the son of John Middlebro, and was educated there and at Osgoode Hall

Osgoode Hall

Osgoode Hall is a landmark building in downtown Toronto constructed between 1829 and 1832 in the late Georgian Palladian and Neoclassical styles. It houses the Ontario Court of Appeal, the Divisional Court of the Superior Court of Justice, and the Law Society of Upper Canada...

. Middlebro was called to the Ontario bar in 1892. He was mayor of Owen Sound

Owen Sound, Ontario

Owen Sound , the county seat of Grey County, is a city in Southern Ontario, Canada...

 from 1905 to 1909. Middlebro was president and chairman of the board of directors for the Grey and Bruce Trust and Savings Company. He was named King's Counsel in 1910. Middlebro served as government whip

Whip (politics)

A whip is an official in a political party whose primary purpose is to ensure party discipline in a legislature. Whips are a party's "enforcers", who typically offer inducements and threaten punishments for party members to ensure that they vote according to the official party policy...

from 1917 to 1919. He was married twice: to Laura J. Tretheway in 1901 and to Pearl Irene Ryan in 1913.