He was the third President of the United States (1801–1809), the principal author of the [[United States Declaration of Independence|Declaration of Independence]] (1776), and one of the most influential Founding Fathers of the United States for his promotion of the ideals of republicanism in the United States. Major events during his presidency include the Louisiana Purchase (1803) and the [[Lewis and Clark Expedition]] (1804–1806). | He was the third President of the United States (1801–1809), the principal author of the [[United States Declaration of Independence|Declaration of Independence]] (1776), and one of the most influential Founding Fathers of the United States for his promotion of the ideals of republicanism in the United States. Major events during his presidency include the Louisiana Purchase (1803) and the [[Lewis and Clark Expedition]] (1804–1806). |