[4][5][6][7][8][9] During his years in Mexico, Luna had served with Francisco Vásquez de Coronado on his expedition to the Seven Cities of Cíbola and crushed an Indian rebellion in Oaxaca.
Luna was chosen by Luís de Velasco, Viceroy of New Spain (Mexico), to establish a settlement on the Gulf Coast of what is now the United States,[9] and clear an overland trade route to Santa Elena (in what is now South Carolina), where another outpost would be founded.
Luna dispatched the factor Luis Daza with a galleon back to Vera Cruz to announce his safe arrival, and plan for resupplying the site.
With much of the colony's stores waiting on the ships, Luna sent several exploring parties inland to scout the area; they returned after three weeks having found only one Indian town.
Lack of food at Nanipacana ultimately spurred Luna to send a 200-man detachment upriver to the Coosa chiefdom (Coça) in Northwest Georgia, where they remained through November before returning to Pensacola Bay.