John Tyler (March 29, 1790 – January 18, 1862) was the 10th President of the United States (1841–1845). He was elected Vice President on the 1840 Whig ticket with William Henry Harrison, and became president after his running mate's death in April 1841. A firm believer in manifest destiny, President Tyler sought to strengthen and preserve the Union through territorial expansion, most famously the annexation of the independent Republic of Texas in his last days in office.Tyler, born to an aristocratic Virginia family of English descent, came to national prominence at a time of political upheaval. In the 1820s, the nation's only political party, the Democratic-Republicans, split into factions, most of which did not share Tyler's strict constructionist ideals. Though initially a Democrat, his opposition to Andrew Jackson and Martin Van Buren led him to ally with the Whig Party. A native of Virginia, Tyler served as a state legislator, governor, U.S. representative, and U.S. senator before his election to national office in 1840. He was put on the ticket to attract disaffected Southerners.Harrison's death made Tyler the first vice president to succeed to the office of President on the death of the incumbent. To forstall a constitutional crisis, Tyler immediately moved into the White House, took the oath of office, and assumed full presidential powers, a precedent that would govern future successions and eventually become codified in the Twenty-fifth Amendment.As president, Tyler opposed the Whig platform and vetoed several Whig party proposals. As a result, most of his Cabinet resigned, and the Whigs, dubbing him His Accidency, expelled him from the party. While he faced a stalemate on domestic policy, he still had several foreign-policy achievements, including the Webster–Ashburton Treaty with Britain and the Treaty of Wanghia with Qing China. Tyler's opposition to federalism and emphatic support of states' rights endeared him to his fellow Virginians but alienated him from most of the political allies who brought him to power in Washington. Tyler dedicated his last two years in office to the annexation of Texas. He sought election to a full term, but he had alienated both Whigs and Democrats and his efforts to form a new party came to nothing. In the last days of his term, Congress passed the resolution authorizing the Texas annexation, which was carried out by Tyler's successor as President, James K. Polk. In retirement, Tyler hoped for a call to return to presidential politics, which never came. He sided with the Confederate government, and won election to the Confederate House of Representatives shortly before his death.