11th United States Vice President, US Senator, US Diplomat. Born in Philadelphia, Pennsylvania, he began his interest in politics while serving as a secretary to Albert Gallatin, who helped negotiate an end to the War of 1812 between the United States and Great Britain. He began his political career in earnest by running for mayor of Philadelphia, which he won, and later, serving as Attorney General for Pennsylvania. He was elected as a Democratic Senator from Pennsylvania to the United States Senate, serving from 1831 to 1833, and was appointed minister to Russia from 1837 to 1839. From 1845 to 1849, he served as the Vice President during the presidency of James K. Polk, and was a loyal supporter of the President. In 1846, he cast the tie-breaking vote over a low tariff bill, voting for the bill which Polk supported. This vote destroyed him politically in his home state of Pennsylvania, as the majority of voters in his state were against the bill, and he never held political office there again. He later served as minister to Great Britain, from 1856 to 1861, and helped settle disputes over the Clayton-Bulwer Treaty (1850), which prevented either Britain or the United States to establish a colony in Central America or to build an Atlantic to Pacific canal (this treaty was later cancelled by the Hay-Pauncefote Treaty of 1901, which allowed for the future building of the Panama Canal). His efforts while serving as minister to Great Britain improved relationships between the two countries. The city of Dallas, Texas is name for him.