William George Thompson (January 17, 1830 – April 2, 1911) was a Civil War officer, trial-court judge, territorial justice, and Republican Representative in the United States House of Iowa's 5th congressional district.

[1] When the Civil War broke out he became a major in the 20th Iowa Volunteer Infantry Regiment.

He then was nominated by President Rutherford B. Hayes as Chief Justice of the Idaho Territorial Supreme Court on January 20, 1879, and was confirmed by the United States Senate three days later.

[2] In April 1879, Thompson resigned as chief justice to run as a Republican to represent Iowa's fifth district in the Forty-sixth Congress, to fill the vacancy caused by the death of Rush Clark.

[1] Returning to the bench, he was elected as judge of Iowa's eighteenth judicial district, serving from 1894 to 1906.