Wordorigins.org

Brunswick is the Low German name for the city of Braunschweig and the surrounding duchy of Brunswick-Lüneberg. It is the ancestral home of the Hanoverian kings of England, George I through William IV. The Hanoverian Dynasty in England ended with the ascension of Victoria, who as a woman could not inherit the Hanoverian throne.

The Canadian province of New Brunswick was named in 1784 in honor of George III’s royal house.

(Sources: Dictionary of Canadian Place Names; Oxford English Dictionary 2nd Edition; Illustrated Dictionary of Place Names)