Editing Andrew Jackson (section)

===First Seminole War===
{{Further|Seminole Wars#First Seminole War|Rhea letter|label1=First Seminole War}}
[[File:Ambristertrial.jpg|thumb|An 1846 [[wood engraving]] by [[William Croome]] of the trial of [[Arbuthnot and Ambrister incident|Robert Ambrister]]  in ''Pictorial Life of Andrew Jackson'' by John Frost|alt=Two soldiers stand trial. Several other men gather around.]]

Following the war, Jackson remained in command of troops in the southern half of the United States and was permitted to make his headquarters at the Hermitage.{{sfn|Remini|1977|p=321}} Appointed as Indian commissioner plenipotentiary, Jackson continued to displace the Native Americans in areas under his command.{{Sfn|Remini|1977|p=322, 325–326}} Despite resistance from Secretary of the Treasury [[William H. Crawford|William Crawford]], he negotiated and signed five treaties between 1816 and 1820 in which the Creek, Choctaw, Cherokee and Chickasaw ceded tens of millions of acres of land to the United States. These included the [[Treaty of Turkeytown]], [[Treaty of Tuscaloosa]], and the [[Treaty of Doak's Stand]].{{sfn|Clark|Guice|1996|pp=233–243}}{{sfn|Wilentz|2005|p=36}}

Jackson soon became embroiled in conflict in Florida. The former British post at [[Negro Fort|Prospect Bluff]], which became known to Americans as "the Negro fort", remained occupied by more than a thousand former soldiers of the British Royal and Colonial Marines, escaped [[runaway slaves|slaves]], and various indigenous peoples.{{sfn|Wright|1968|p=569}} It had become a magnet for escapees{{sfn|Wright|1968|p=569}} and was seen as a threat to the property rights of American enslavers,{{sfn|Porter|1951|pp=261–262}} even a potential source of insurrection by enslaved people.{{sfn|Missall|Missall|2004|p=26}} Jackson ordered Colonel [[Duncan Lamont Clinch|Duncan Clinch]] to capture the fort in July 1816. He destroyed it and killed many of the garrison. Some survivors were enslaved while others fled into the wilderness of Florida.{{sfn|Missall|Missall|2004|pp=28–30}}

White American settlers were in constant conflict with Native American people collectively known as the [[Seminole]]s, who straddled the border between the U.S. and Florida.{{sfn|Missall|Missall|2004|pp=32–33}} In December 1817, Secretary of War [[John C. Calhoun]] initiated the [[Seminole Wars#First Seminole War|First Seminole War]] by ordering Jackson to lead a campaign "with full power to conduct the war as he may think best".{{sfn|Mahon|1998|p=64}} Jackson believed the best way to do this was to seize Florida from [[History of Spain (1808–1874)|Spain]] once and for all. Before departing, Jackson wrote to President [[James Monroe]], "Let it be signified to me through any channel ... that the possession of the Floridas would be desirable to the United States, and in sixty days it will be accomplished."{{sfn|Ogg|1919|p=66}}

Jackson invaded Florida, captured the Spanish fort of [[San Marcos de Apalache Historic State Park#History|St. Marks]], and occupied [[Pensacola, Florida|Pensacola]]. Seminole and Spanish resistance was effectively ended by May 1818. He also captured two [[British subject]]s, [[Arbuthnot and Ambrister incident|Robert Ambrister and Alexander Arbuthnot]], who had been working with the Seminoles. After a brief trial, Jackson executed both of them, causing an [[international incident]] with the British. Jackson's actions polarized Monroe's cabinet. The occupied territories were returned to Spain.{{sfn|Mahon|1998|pp=65–67}} Calhoun wanted him censured for violating the Constitution, since the United States had not [[Declaration of war by the United States|declared war]] on Spain. [[United States Secretary of State|Secretary of State]] John Quincy Adams defended him as he thought Jackson's occupation of Pensacola would lead Spain to sell Florida, which Spain did in the [[Adams–Onís Treaty]] of 1819.{{sfn|Wilentz|2005|pp=38–39}} In February 1819, a congressional investigation exonerated Jackson,{{sfn|Heidler|1993|p=518}} and his victory was instrumental in convincing the Seminoles to sign the [[Treaty of Moultrie Creek]] in 1823, which surrendered much of their land in Florida.{{sfn|Mahon|1962|pp=350–354}}