Long expedition

The Long Expedition was an 1819 attempt to take control of Spanish Texas by filibusters. It was led by James Long and successfully established a small independent government, known as the Republic of Texas (distinct from the later Republic of Texas created by the Texas Revolution). The expedition crumbled later in the year, as Spanish troops drove the invaders out. Long returned to Texas in 1820 and attempted to reestablish his control.

Beginning in 1810, Spanish territories in North and South America began to revolt. In particular, the Mexican War of Independence made it difficult for Spain to adequately protect its more remote territories such as Texas. Lured by the promise of free land and potential wealth, many men from the United States joined expeditions to try to take Texas from Spain. The expeditions were largely planned in New Orleans, and variously wished to establish an independent republic in Texas or assist the revolutionaries fighting within Mexico. For the first nine years of the revolt, ownership of Texas was contested. The United States claimed that the Louisiana Purchase included all of Texas, while Spain believed the boundary rested at the Red River, leaving Texas under Spanish control. The Texans later had a revolt which led to their independence.

In early 1819, Spain and the United States signed the Adams–Onís Treaty, which established the boundary of the Louisiana Purchase at the Sabine River. Many Americans were outraged that the United States had abandoned any claim to Texas. Rhetoric was especially high in Natchez, Mississippi. James Long, a doctor, was one of the most vehement voices against the treaty. Public sentiment in Natchez soon swung to military action to take back territory they were convinced belonged to them. Men began to gather in Natchez for an invasion of Texas. They soon elected Long as their leader, although his only prior military experience had been as a surgeon in the War of 1812. The Natchez newspaper opined that "Never was [there] a more propitious moment for effecting their purpose." By the end of June, Long had received pledges for over $500,000, and about 200 men, including James Bowie and Ben Milam, had gathered for the expedition.

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