BOSQUE-LARIOS EXPEDITION. On April 30, 1675, Fernando del Bosque, Fray Juan Larios, Fray Dionisio de San Buenaventura, ten Spanish soldiers, Lázaro Agustín, governor of the Indian pueblo of San Miguel de Luna, Capt. Juan de la Cruz, and twenty Bobole Indians set out from the mission of Nuestra Señora de Guadalupe, at the site of present Monclova, Coahuila, to convert the Indians of the Coahuila. On the Nadadores River they were joined by a hundred Guyquechale Indians. The expedition reached the Río Sabinas (Coahuila) on May 5, erected a cross, and took formal possession of the river. On May 11 it reached the Rio Grande, probably a little below the present site of Eagle Pass. Bosque took formal possession of the river, erected a wooden cross, and renamed the river the San Buenaventura del Norte. On May 15 the expedition was met by several Indian chiefs, who asked the missionaries to come to teach and baptize their followers. The oath of allegiance to the king was administered to all the Indians, a portable altar was set up, and Mass was celebrated.
Full article on the Texas State Historical Association's Handbook of Texas Online