The Federalist Era’s strengthening of federal government, the peaceful transfer of power in the Election of 1800, and the expansive territorial gains of the Jeffersonian Era, most notably the Louisiana Purchase, all contributed to the Early Republic of the United States (1790–1820s) being a crucial period. The period also saw the nation’s assertiveness in the War of 1812 against Britain, a surge of national unity during the “Era of Good Feelings” under Monroe, and the initial forays into addressing the North-South divide with the Missouri Compromise of 1820.