Thomas Jefferson Third President of the United States of America. Thomas Jefferson Thomas Jefferson (1743-1826) was the third president of the United States and a creator of the Declaration of Independence. Thomas Jefferson was a philosopher, politician, scientist, architect, inventor, musician, and writer. Thomas Jefferson was also one of the smartest leaders in history. His father was named Peter Jefferson, a very rich Farmer from Virginia. Thomas’s Mother, Jane Randolph Jefferson, was part of the Randolph family. The Randolph Family was a big part of Virginia history, and also very rich also. Peter and