Armed rebels storm Fort San Carlos at Baton Rouge early in the morning on September 23, 1810 and kill two Spanish soldiers.

The rebels unfurl the flag of the new republic, a single white star on a blue field.

After the successful attack, organized by Philemon Thomas, plans are made to take Mobile and Pensacola from the Spanish and incorporate the eastern part of the province into the new republic.

Thomas, born in Virginia, had served in the American forces during Revolutionary War and later moved to Kentucky.

He was a member of Kentucky's Constitutional Convention and served in the state House and state Senate before moving to Louisiana in 1806.

Reuben Kemper leads a small force in an attempt to capture Mobile, but the expedition ends in failure.

Born in Fauquier County, Virginia, Kemper and his brothers Nathan and Samuel had settled in Feliciana Parish, near Baton Rouge, Spanish West Florida, shortly after 1800.

Expelled from the province by the Spanish authorities in a dispute over land titles, the Kemper brothers had organized a small force in the Mississippi Territory and returned, declaring West Florida to be independent.

They had attempted to capture Baton Rouge in 1804, but were defeated, having failed to gain the support of local Anglo-American settlers.

Most of the latter were satisfied with Spanish rule on account of Spain's liberal land grants and its protection of slavery.

The following year Spanish forces had captured all three brothers while they were on U.S. soil, but American forces had rescued them as they were being taken down the Mississippi River.

In 1810, during the rebellion against Spanish rule by British and Anglo-American settlers (who comprised the majority of inhabitants), Reuben Kemper and Joseph White are authorized to invite the inhabitants of Mobile and Pensacola to join in the revolt.

When Kemper crosses into the Mississippi Territory, U.S. forces arrest  him, as they do not wish to provoke Spain into war and fear Kemper's intentions.

He is more fortunate than his colleagues, who are seized by the Spanish authorities and sent as prisoners to El Morro, in Havana, Cuba, but the rebellion spreads.

Support for the revolt is far from unanimous, due to the presence of competing pro-Spanish, pro-American, and pro-independence factions, as well as the presence of scores of foreign agents.

The faction that favors the continued independence of West Florida secures the adoption of a constitution at a convention in October.

The convention had earlier commissioned an army under General Philemon Thomas to march across the territory, subdue opposition to the insurrection, and seek to secure as much Spanish-held territory as possible.

"Residents of the western Florida Parishes proved largely supportive of the Revolt, while the majority of the population in the eastern region of the Florida Parishes opposed the insurrection. Thomas' army violently suppressed opponents of the revolt, leaving a bitter legacy in the Tangipahoa and Tchefuncte River region." (Christina Chapple, quoting Southeastern Louisiana history professor Sam Hyde, in "Commission planning for West Florida Republic bicentennial" on the Southeastern Louisiana University web site, posted July 6, 2009 (accessed March 25, 2018).

The boundaries of the newly declared Republic of West Florida include all territory south of parallel 31°N, east of the Mississippi River, and north of the waterway formed by the Iberville River, Amite River, Lake Maurepas, Pass Manchac, Lake Pontchartrain, and the Rigolets.

The Pearl River with its branch that flows into the Rigolets forms the eastern boundary of the republic.

On October 27, 1810, U.S. President James Madison had proclaimed that the United States should take possession of West Florida between the Mississippi and Perdido Rivers, based on a tenuous claim that it is part of the Louisiana Purchase.

The West Florida government opposes annexation, preferring to negotiate terms to join the Union.

Governor Fulwar Skipwith proclaims that he and his men will "surround the Flag-Staff and die in its defense."

William C. C. Claiborne is sent to take possession of the territory, entering the capital of St. Francisville with his forces on December 6, 1810.

Fulwar Skipwith, elected as governor of the Republic of West Florida on November 7, together with members of a bicameral legislature, had been inaugurated on November 29.

A week later, he and many of his fellow officials still lingered at St Francisville preparing to go to Baton Rouge, where the next session of the legislature is to consider his ambitious program.

The impending U.S. takeover apparently comes as a surprise to Skipwith when the Mississippi Territory governor, David Holmes, and his party approach the town.

Holmes persuades all except a few leaders, including Skipwith and Philemon Thomas, the general of the West Florida troops, to acquiesce to American authority.

Skipwith complains bitterly to Holmes that, as a result of seven years of U.S. tolerance of continued Spanish occupation, the United States has abandoned its right to the country and that the West Florida people will not now submit to the American government without conditions.

Skipwith and several of his unreconciled legislators now depart for the fort at Baton Rouge, rather than surrender the country unconditionally and without terms.

At Baton Rouge on December 9, Skipwith had informed Holmes that he would no longer resist but cannot speak for the troops in the fort.

Their commander is John Ballinger, who upon the assurance of Holmes that his troops would not be harmed, had agreed to surrender the fort.

The Orleans Territory governor, William C. C. Claiborne and his armed forces from Fort Adams, land  two miles above the town.

Holmes reports to Claiborne that "the armed citizens ... are ready to retire from the fort and acknowledge the authority of the United States" without insisting upon any terms.

Claiborne agrees to a respectful ceremony to mark the formal act of transfer.

Thus, at 2:30 p.m. this afternoon, December 10, 1810, "the men within the fort marched out and stacked their arms and saluted the flag of West Florida as it was lowered for the last time, and then dispersed."