William Allain, American soldier and politician, 58th Governor of Mississippi (born 1928)

William A. Allain was an American politician and lawyer who held office as the 59th governor of Mississippi as a Democrat from 1984 to 1988. Born in Adams County, Mississippi, he attended the University of Notre Dame and received a law degree from the University of Mississippi School of Law in 1948.

The governor of Mississippi is the head of government of Mississippi and the commander-in-chief of the state's military forces. The governor has a duty to enforce state laws, and the power to either approve or veto bills passed by the Mississippi Legislature, to convene the legislature at any time, and, except in cases of treason or impeachment, to grant pardons and reprieves.