What did Martin Van Buren do while he was in office?

Martin Van Buren (1782–1862) served as president (1837–41) after Andrew Jackson. He had been Jackson's vice president, and he sought to continue Jackson's policies in many areas. Van Buren was also a founder of the Democratic party.
As soon as Van Buren entered the White House, the country faced an economic crisis called the Panic of 1837. One reason for the economic tumult was Jackson's decision to transfer federal funds into state banks. Many of those state banks failed. Van Buren worked to rectify the country's shaky finances, and he supported the establishment of the Independent Treasury System. He did not, however, help those ordinary Americans who suffered during the economic crisis.
Van Buren continued Jackson's harsh policies towards Native Americans. These included another war against the Seminoles in Florida and the transfer of Indians to regions West of the Mississippi River.
Tensions between North and South were high during his presidency. He blocked Texas from joining the Union, and this damaged his standing in the South.
The economic crisis and his stand on the question of Texas's admission cost him the presidency. He was badly defeated in the presidential election of 1840.