Before, however, any actual contest arose over the question, France sold Louisiana to the United States, with the same vague description of boundary contained in the cession of the territory from Spain to France by the Treaty of St. Ildefonso. The question of boundary became now one which must be settled between Spain and the United States. The United States claimed at once that Louisiana reached to the Perdido. Spain disputed the claim, and held that Florida extended to the Iberville and the Lakes. Spain could make out the better abstract of title. Spain certainly did not intend to recede to France in 1800 anything more as Louisiana than France had ceded to her in 1762. But the United States had a show of legal title. It could be held that the ancient boundary of Louisiana was the one intended both in the Treaty {24} of St. Ildefonso and in that of 1803, in which France passed the possession of Louisiana to the United States. The reasons of physical geography and of national development certainly favored the annexation of the whole of Florida to the United States; and with such forces to back the apparent legal claim to a large part of it, the result of the dispute could not well have been otherwise than it was. The United States enforced its claim by military occupation of the disputed district before the close of the War of 1812. [Sidenote: Occupation of Florida by the United States forces during the War of 1812.] During the course of the war, the British forces had occupied Pensacola. The Spanish governor either could not, or would not, prevent them from doing so. Florida became thus, in spite of its nominal neutral status, a base of operations for the enemy of the United States. No more convincing evidence of the necessity for its annexation to the United States could have been offered. It was thus seen that not only the geography and the national growth of the Union demanded it, but that the safety of the Union, in case of war with any power, required it. The sea is the natural boundary of the United States on the south, and it was the "manifest destiny" of the Union to reach it.