William Gannaway Brownlow (born August 29, 1805) was a Republican senator from Tennessee who served one term in the United States Senate from March 4, 1869, to March 3, 1875. Representing the state of Tennessee at large, he held office during the Reconstruction era and was affiliated with the Republican Party. His tenure in the Senate marked his principal role in national politics.

Brownlow’s service in the Senate spanned a single term, and he is recorded as a former officeholder. Identified in congressional records by the biographical guide ID B000963, he is recognized as a historical member of Congress from Tennessee. Further details of his committee assignments, office contact information, or additional roles are not provided in the available metadata.