アダムズ＝オニス条約
From the Spanish point of view, Florida was a failure. Iti did not produce anything the Spaniards wanted. The three garrisons were a financial drain, and it was not felt desirable to send settlers or additional garrisons. The Crown decided to cede the territory to the United States. It accomplished this through the Adams–Onís Treaty of 1819, which took effect in 1821.