Through his father's line, the family claimed direct descent from Lord Parr, Baron Kendal, who was a well-known nobleman, in the north of England, in the reign of Henry VIII, whose arms of their family are to be seen in the Parr Chapel of Kendal Church, Westmorland.

[1] At the age of 19. he joined the British Army's 20th Regiment of Foot as an ensign and saw service in the War of the Austrian Succession.

A subaltern officer, he was with the Prince William, Duke of Cumberland, whose army marched through Scotland against Charles Stuart's Jacobite rising at the Battle of Culloden in 1746.

His predecessor, Francis Legge, had been an absentee governor for six years since he had been recalled to England, and the colony had been under the stewardship of a succession of military lieutenant-governors.

In 1786, when the colonial administration of British North America was reorganized, Parr had hoped to be named to the new position of Governor-General of The Canadas and Governor-in-Chief of British North America but was disappointed when the position went to Guy Carleton who was elevated to the peerage as Lord Dorchester.

Parr's administration oversaw the settlement of Black Nova Scotians, who were African-American Loyalists fleeing the United States.

He attempted to establish a whaling industry in Dartmouth (see Quaker Whaler House), and was embroiled in the "judges' affair" in which lawyers accused him of appointing incompetent or biased jurists to the bench.