Abraham Alfonse Albert Gallatin ( January 29 , 1761 -- August 12 , 1849 ) was a Swiss-American politician , diplomat , ethnologist and linguist . He served as a Congressman , Senator , United States Ambassador and was the longest-serving United States Secretary of the Treasury .
Abraham Alfonse Albert Gallatin ( January 29 , 1761 -- August 12 , 1849 ) was a Swiss-American ethnologist , linguist , politician , diplomat , Congressman , and the longest-serving United States Secretary of the Treasury .