The Burr conspiracy was a plot alleged to have been planned by Aaron Burr in the years during and after his term as Vice President of the United States under US President Thomas Jefferson. According to the accusations against Burr, he attempted to use his international connections and support from a cabal of US planters, politicians, and army officers to establish an independent country in the Southwestern United States, parts of Mexico, and Florida. Burr's version was that he intended to farm 40,000 acres (160 km2) in the Texas Territory which had been leased to him by the Spanish Crown.

Aaron Burr Jr. was an American politician, businessman, lawyer, and Founding Father who served as the third vice president of the United States from 1801 to 1805 during Thomas Jefferson's first presidential term. He founded the Manhattan Company on September 1, 1799. Burr is remembered for his famous personal and political conflict with Alexander Hamilton, which culminated in the Burr–Hamilton duel in Weehawken, New Jersey on July 11, 1804. Burr mortally wounded Hamilton, who died from his wounds the following day.