In the 1783 peace treaty, Great Britain returned both Florida colonies to Spanish control. Instead of administering Florida as a single province, as it had prior to 1763, New Spain preserved the British arrangement of dividing the territory between East and West Florida (Florida Oriental and Florida Occidental).[6] When Spain acquired West Florida in 1783, the eastern British boundary was the Apalachicola River, but Spain in 1785 moved it eastward to the Suwannee River.[7][8] The purpose was to transfer San Marcos and the district of Apalachee from East Florida to West Florida.[9][10]