The longest-serving governor of all time was Terry Branstad of Iowa, who was elected to his sixth (non-consecutive) term in 2014. Governor Branstad resigned on May 24, 2017 to become the United States Ambassador to China. He held the title of Governor of Iowa for 22 years. On December 14, 2015, he became the longest-serving governor in US history, breaking the record held by George Clinton of New York, who served 21 years from 1777 to 1795 and from 1801 to 1804.