The Virgen del Rosario is the patron saint of the Dominican Order, who were in charge of the slave brotherhoods in colonial times. This is why the image of the saint is often accompanied by an icon featuring the letter "S" pinned on by a nail, symbolizing the black slaves. Worship of the saint dates back to 1 536, and the festival is celebrated all over Peru. On the first Sunday of October, in Cajatambo, in the highlands of the department of Lima, the locals hold an agricultural fair, bullfights, marinera competitions and a procession featuring Los Diablos (demons) as the main dance act.

In the district of Urcos, in the province of Quispicanchis, as well as in Combate and Checaupe, in the province of Canchis, department of Cusco, locals celebrate the date with processions, bullfights and pachamancas, a dish prepared in underground pits and cooked over hot stones.

The center of all Virgen del Rosario celebrations however is the northern Andean department of Ancash. The celebrations are highlighted by the presence of pallas, ladies dressed in costumes with wide sleeves and tall crowns of flowers, and the famous negritos, dancers dressed in black wool masks who liven up the celebration.

This festival features a symbolic confrontation between the Moors, locals dressed in Andean costume, and the Christians, who are dressed in Spanish outfits harking back to colonial times. The battle ends when the Moorish kings, having been vanquished and taken prisoner, repent and beg to be converted to Christianity. As dusk falls, the virgin's procession sets off back to church, accompanied by bands of musicians.