In 1803, Jefferson convinced Congress to purchase the Louisiana Territory from France, which caused America to expand from its original thirteen colonies, proving that the America is becoming a strong independent land that other countries were beginning to be terrified of. Thomas Jefferson believed that “the United States of America are united by covenant under the style and title of one Constitution for the United States, and amendments… and by the Constitution which no power over freedom of religion, over freedom of speech, or freedom of the press is delegated to the United States" (MP 6-6, 156). President Jefferson then decided to make informed decisions regarding the westward expansion of the United States. Then another expansion was made by the expedition led by Captain Meriwether Lewis and the man he chose to accompany him as co-leader of the voyage, William Clark. Together, and with considerable help from their Native American guide Sacagawea, and native tribes along the way, they managed to explore much of the continent. The impact of the Lewis and Clark expedition involved the considerable knowledge that the explorers acquired during their journey regarding the geographical characteristics of the territory and the peoples who populated it. Clark states that “[we] believe that the surest guarantee of wild loyalty to anyone