William M. Hancock

William M. Hancock (1817/1818 - March 8, 1891) was a judge and state legislator in Mississippi. His father was Judge Jubal Braxton Hancock.

The Clarion-Ledger identified him as a Radical Republican in 1869.

Hancock served in the provisional legislature in 1870 as president pro-tem of the Mississippi State Senate. He represented the 9th District, or Jasper County, from 1870 to 1871. John R. Lynch's book on Reconstruction reported him to be the only Republican legislator to vote against Hiram R. Revels as nominee to the U.S. Senate. Lynch said Hancock believed an African American could not legally serve in the body.

He served as postmaster in Meridian, Mississippi, having been appointed by presidents Chester Arthur before being ousted by Grover Cleveland, and was reappointed by Benjamin Harrison. He died of pneumonia at 5 AM on March 8, 1891, aged 73. His widow Mary Jane Hancock was nominated to take his place after his death.