1911 Encyclopædia Britannica/Opata
OPATA ("enemies," so called by their neighbours the Pimas), a tribe of Mexican Indians of Piman stock. Their country is the mountainous district of north-eastern Sonora and north-western Chihuahua, Mexico. Though usually loyal to the Mexican government, they rebelled in 1820, but after a gallant effort were defeated. They number now about 5000, and still largely retain their ancient autonomy.