William O'Neil (September 20, 1848 – March 3, 1917) was an American merchant, temperance advocate, and Republican politician.

[1] O'Neil was born in the town of Scott, Columbia County, Wisconsin, on September 20, 1848.

[3] In 1892 he was elected to the Wisconsin State Assembly, from the vast district of Bayfield, Burnett, Sawyer, and Washburn counties.

The 4th Wisconsin Infantry, however, never saw any combat in the war and spent just a few months on garrison duty in Alabama.

Spooner then assisted O'Neil in receiving an appointment as superintendent of the Leech Lake Indian Reservation, where he lived for the rest of his life.