Born in Sheboygan, Wisconsin, Marotz graduated from Shawano High School.

During World War II, Marotz served in the United States Marine Corps in the Pacific Theater from August 1941 to November 1943.

He was sent to Officer Candidate School at Bowling Green State University and Dartmouth College.

[2] He served five terms from Shawano County, Wisconsin in the Legislature, as Majority Leader from 1955 to 1957, and was elected Speaker of the Assembly from 1957 to 1959.

After the conclusion of World War II he returned to the study of law in the office of a lawyer and passed the bar exam.