SEATTLE -

Billy Frank Jr., the tribal fisherman who led the Northwest "fish wars" that helped restore fishing rights for American Indians four decades ago, has died at age 83.

The Northwest Indian Fisheries Commission on Monday confirmed his death.

Frank was first arrested for salmon fishing as a boy in 1945 -- an event that led him on a long campaign for tribal rights. He and others were repeatedly arrested as they staged "fish ins" demanding the right to fish in their historical waters, as they were guaranteed in treaties when they ceded land to white settlers in the 19th century.

In 1974, U.S. District Judge George Boldt affirmed the tribes' right to half of the fish harvest -- and the nation's obligation to honor the old treaties.

Frank continued to be an environmental leader and activist for salmon recovery.