Charles Ernest Grassley (born September 17, 1933) is an American politician serving as the senior United States senator from Iowa, having held the seat since 1981. Grassley was first elected to the Senate in 1980 and has been reelected seven times. He is the longest-serving Republican in Congressional history and the sixth-longest-serving U.S. senator in history. Before becoming a senator, Grassley served eight terms in the Iowa House of Representatives (1959–1975) and three in the United States House of Representatives (1975–1981). He has served three stints as Senate Finance Committee chairman during periods of Republican Senate majority. Upon the retirement of Orrin Hatch on January 3, 2019, Grassley became the Senate's most senior Republican and its president pro tempore. Upon Patrick Leahy's retirement in January 2023, Grassley became the most senior member of the Senate. At 90 years, 5 months and 23 days of age, Grassley is the oldest sitting United States senator. He is the president pro tempore emeritus of the United States Senate. During his four decades in the Senate, Grassley has chaired the Senate Finance Committee, the Senate Narcotics Caucus, the Senate Judiciary Committee, and the Senate Aging Committee.