On November 26, 1890, Treadwell married Grace B. Dill of Prescott, Wisconsin, who he had four children with.

[2] Twichell was elected to two terms in the North Dakota House of Representatives, in 1895 and 1897.

In 1908, Twichell was nominated for governor at the Progressive Republican Convention but lost to his opponent in the primary.

He was known as an advocate of reform legislation and battled aggressively against boss rule in state politics.

He is credited with building the first gravel highway in North Dakota and organizing the first cooperative grain elevator enterprise in the state.