Perhaps the most important event in the early part of Monroe's administration was the Seminole war. Those Indians occupied Florida, and could hide themselves in the swampy everglades and defy pursuit. Many runaway slaves found safe refuge there, intermarried with the Seminoles, and made their homes among them. They were not always fairly treated by the whites, and committed many outrages on the settlers in Georgia and Alabama. When the Creeks, who insisted they had been cheated out of their lands, joined them, General Gaines was sent to subdue the savages. He failed, and was caught in such a dangerous situation that General Jackson hastily raised a force and marched to his assistance. Since Florida belonged to Spain, Jackson was instructed by our government not to enter the country except in pursuit of the enemy. "Old Hickory" was not the man to allow himself to be hampered by such orders, and, entering Florida in March, 1818, he took possession the following month of the Spanish post of St. Mark's, at the head of Appalachee Bay. Several Seminoles were captured, and, proof being obtained that they were the leaders in a massacre of some settlers a short time before, Jackson hanged every one of them. Advancing into the interior, he captured two British subjects, Robert C. Ambrister, an Englishman, and Alexander Arbuthnot, a Scotchman. There seemed to be no doubt that the latter had been guilty of inciting the Indians to commit their outrages, and both were tried by court-martial, which sentenced Arbuthnot to be hanged and Ambrister to receive fifty lashes and undergo a year's imprisonment. Jackson set aside the verdict, and shot the Englishman and hanged the Scotchman. He then marched against Pensacola, the capital of the province, drove out the Spanish authorities, captured Barrancas, whose troops and officials were sent to Havana. [Illustration: AN INDIAN'S DECLARATION OF WAR.] Jackson carried things with such a high hand that Spain protested, and Congress had to order an investigation. The report censured Jackson; but Congress passed a resolution acquitting him of all blame, and he became more popular than ever. Spain was not strong enough to expel the Americans, and she agreed to a treaty, in October, 1820, by which East and West Florida were ceded to the United States, the latter paying Spain $5,000,000. The Sabine River, instead of the Rio Grande, was made the dividing line between the territories of the respective governments west of the Mississippi. Jackson was the first governor of Florida, and, as may be supposed, he had a stormy time, but he straightened out matters with the same iron resolution that marked everything he did. STATES ADMITTED--THE MISSOURI COMPROMISE.