Thomas Jefferson (April 13, 1743 – July 4, 1826) was an American statesman, diplomat, lawyer, architect, philosopher, and Founding Father who served as the third president of the United States from 1801 to 1809. Thomas Jefferson (April 13, 1743 – July 4, 1826) was an American statesman, diplomat, lawyer, architect, philosopher, and Founding Father who served as the third president of the United States from 1801 to 1809. He previously served as the second vice president of the United States from 1797 to 1801. In 1752, at age nine, he began attending a local school run by a Scottish Presbyterian minister and also began studying the natural world, which he grew to love.