 The first settlement to be founded on the Lower Río Grande was that of Nuestra Señora de Santa Ana de Camargo.It was founded on March 5, 1749, with the dedication to Señora Santa Ana by captain Don Blas María de la Garza Falcón at the eastern edge of the San Juan River near its confluence with the Río Grande.The foundation had 85 families – a total of 531 persons.