Louise Arbour, a former Supreme Court of Canada justice who later served as a United Nations commissioner and prosecuted war crimes in the former Yugoslavia and Rwanda, has been named as Canada’s new Governor-General.

Ms. Arbour succeeds Mary Simon, an Inuk and advocate for Inuit rights who became the first Indigenous person to hold the title when she was appointed by then prime minister Justin Trudeau in 2021.

“As Mary Simon has, Louise Arbour will represent the best of Canada to Canadians and the world,” Prime Minister Mark Carney said Tuesday, in remarks prepared for delivery at an announcement ceremony at the National Gallery of Canada.

Ms. Arbour, 79, was born in Montreal. She taught at Osgoode Hall Law School and first became a judge in Ontario in the late 1980s. She was a justice on the Supreme Court from 1999 until 2004.