Walter Jeremiah Maddock was an American politician in North Dakota, US. He served in the North Dakota House of Representatives from 1915 to 1923, and became the 14th Lieutenant Governor of North Dakota in 1925. Maddock became the 15th Governor of North Dakota in 1928 when Arthur G. Sorlie died in office. He was the first governor born in what would eventually become North Dakota.

The lieutenant governor of North Dakota is a political office in North Dakota. The lieutenant governor's duty is to preside as President of the Senate, and is responsible for legislative relations, the state budget and agribusiness development. In the event the office of the governor becomes vacant, the lieutenant governor assumes that office and appoints a replacement lieutenant.