The Seminole War, also known as the Florida Wars, is often treated as one long conflict in Florida between the Seminole and the United States, generally dated from 1816 to 1858. Aggravated by broken promises and failed negotiations over more than four decades, it grew out of the United States government's desire to control Florida for defense and commerce, American settlers' push into territory long occupied by the Seminole, and the presence of escaped slaves seeking refuge in Spanish Florida, where slavery had been outlawed. Florida was an unsettled land marked by unrest, weak Spanish control, ignored property rights, and many languages. American expansion into the Spanish-controlled peninsula began in the 1700s, and earlier efforts known as the Patriot Wars of East Florida failed, but after Florida became American territory in 1821, conflict between the U.S. and the Seminole escalated again. To ease tensions, the U.S. government moved the Seminole to a reservation under the Treaty of Moultrie Creek in 1823, enforced by forts in the territory and an Indian Agent near Fort King serving as a liaison. Even between the three distinct war years, tension and conflict remained constant, helping explain why many see a single war rather than three. The struggle lasted so long because the Seminole excelled at guerrilla warfare and knew the land intimately, while the U.S. Army suffered from inadequate funding and resources, changing leadership and strategy, and an inability to endure Florida's oppressive summer climate, forcing troops to withdraw in summer and allowing the Seminole to regroup.