The major impact of the Louisiana Purchase on the United States was the vast expansion of its territory, effectively doubling the size of the nation. Acquired from France in 1803 for approximately $15 million, this land deal included land that would become parts of 15 future states. The acquisition provided the U.S. with immense natural resources, agricultural land, and strategic advantages for trade and westward expansion. It also fueled the idea of Manifest Destiny, encouraging settlement and exploration. However, it also raised issues concerning slavery and relations with Native American tribes in these newly acquired lands.