John David Dingell Jr. (July 8, 1926 – February 7, 2019) was an American politician from the state of Michigan who served as a member of the United States House of Representatives from 1955 until 2015. A member of the Democratic Party, Dingell holds the record as the longest-serving member of Congress in American history.

Born in Colorado Springs, Colorado, Dingell attended Georgetown University, where he earned a Bachelor of Science in chemistry in 1949 and a Juris Doctor in 1952. Dingell began his congressional career by succeeding his father, John Dingell Sr., as representative for Michigan's 16th congressional district on December 13, 1955. A longtime member of the House Energy and Commerce Committee, Dingell chaired the committee from 1981 to 1995 and from 2007 to 2009. He was Dean of the House of Representatives from 1995 to 2015. Dingell was instrumental in the passage of the Medicare Act, the Water Quality Act of 1965, the Clean Water Act of 1972, the Endangered Species Act of 1973, the Clean Air Act of 1990, and the Affordable Care Act, among other laws. He also helped to pass the Civil Rights Act of 1964. Dingell was one of the final two World War II veterans to have served in Congress; the other was Texas Representative Ralph Hall.

Dingell announced on February 24, 2014 that he would not seek reelection to a 31st term in Congress. His wife, Debbie Dingell, successfully ran to succeed him in the 2014 election. President Barack Obama awarded Dingell the Presidential Medal of Freedom in 2014. Dingell left office on January 3, 2015.