Thomas Jefferson, American president. Jefferson (1743-1826) was the primary author of the Declaration of Independence and one of the major figures of early American political history. After serving as the nation's first Secretary of State (1790-1793) and as Vice-President to John Adams (1797-1801), he was elected the third president of the USA, holding office from 1801-1809. (Photo by Ann Ronan Pictures/Print Collector/Getty Images)