William Ellis Niblack (May 19, 1822 – May 7, 1893) was a politician and judge who served as a U.S. Representative from Indiana, a judge on the Indiana Supreme Court, and a member of both the Indiana Senate and the Indiana House of Representatives Niblack was born in Dubois County, Indiana, a cousin of Silas Leslie Niblack. He attended the country schools and Indiana University at Bloomington. He studied law and was admitted to the bar in 1843 and commenced practice in Vincennes, Indiana.