Frederick Robert[1] Zimmerman (November 20, 1880 – December 14, 1954) was a German American politician from Milwaukee, who served as the 25th Governor of Wisconsin.

Zimmerman's father, a molder, died when he was 5 and at an early age he began contributing to the support of his family by selling newspapers.

He left this job, after his marriage, to take a position as a traveling salesman with the Pfister & Vogel Leather Company, and also worked as a bookkeeper for a Milwaukee lumber firm.

[3] He was an active member of the Progressive faction of his party, but served only one term (1909–1910), losing the 1910 election in a four-way contest to Socialist James H. Vint with 1521 votes, to 1501 for Zimmerman, 143 for McLogan, and 12 for Prohibitionist William H.

When the Progressives refused to endorse him in the gubernatorial election in 1926 (because of his failure to support the 1924 presidential candidacy of Robert M. La Follette Sr.),[7] Zimmerman ran in the Republican primary election as an "independent" against both Progressive (Herman Ekern) and Stalwart (Charles B. Perry) candidates, as well as another "independent".