Early Spanish explorers encountered a number of ethnically distinct bands of aboriginal peoples near the Medina River who spoke a common Coahuiltecan dialect.
[4] Their homeland was well removed from the usual northern Spanish trade routes and trails leading into Tejas.
[2] When the Espinosa-Olivares-Aguirre expedition—Spain's initial excursion to explore the area of the San Antonio River valley—crossed the Medina on April 24, 1709, they encountered the Pastia tribe for the first time.
The Pastia, as well as the other tribes of the southeastern Texas tidal plain, reportedly subsisted in the lean months on roots; raw insects, lizards, and worms; and the undigested nuts picked from deer dung.
[3][2][5] Records from the time tell of the Pastias and other Indian tribes of the area having encampments in the vicinity of the Spanish missions of San Antonio during their early construction, a period spanning 1707 through 1737.
[2][1] The tribes of southeastern Tejas suffered a severe decline in population following repeated epidemics of diseases to which they had no immunity, starting about the time of, or shortly before, the mission network's construction.
[2][4] Following the decline of the Pastia and their neighboring tribes, the lands that were once their homes and the southeastern Texas coastal plains were eventually inhabited by the Apache.