Spanish efforts to colonize Tampa Bay in the 1500s resulted in disaster for all. The Calusa and Timucua Indians met the strong-arm tactics of the explorers with both trickery and might. When the Spaniards finally gave up, they'd left behind diseases that wiped out the native communities.
In 1757, Don Francisco Maria Celi returned, noting, "The natives give this bay the name Tampa," and he explored the river as far north as Hillsborough River State Park. Again Tampa was forgotten by outsiders, until 1824 when Fort Brooke was established to oversee the Seminole Indians in the area. The fort, which became a hub for the military in the Seminole Wars, both hampered and encouraged the development of Tampa as a city. The first post office was established in 1831, Tampa was designated the county seat, and the sale of land began albeit slowly.