John Bolivar Cassoday (July 7, 1830 – December 30, 1907) was an American lawyer, politician, and judge.

After one year at the University of Michigan, he attended the Albany Law School.

He moved to Janesville, Wisconsin, in July 1857 and established a law practice.

[2][3] Later in 1880, Cassoday was appointed to the Wisconsin Supreme Court by Governor William E. Smith, to fill the vacancy caused by the death of Chief Justice Edward George Ryan.

Cassoday served twelve years as Chief Justice until his death in 1907.