[2] Colonel Alejandro Bezada, then Prefect of Arequipa, organized a division of 560 men, whose command he himself assumed, setting off southward in the first half of April 1879.

After the defeat, the unit marched to San Lorenzo de Tarapacá, where on 27 November 1879 the battle of the same name would take place and in which the battalion to which Mariano Santos belonged would be entrusted the defense of it.

During the combat, which took place in the streets of the town, Santos, with a bayonet in hand, managed to seize the war ensign of the Chilean regiment after a bloody fight in which the entire escort perished.

These individuals, fighting like lions in defense of their beloved deposit, all perished at their posts, and before they died, three of the last to fall took the timely precaution of burning the banner, rather than allow it to be insulted and sullied by the enemies of their country.

In a solemn ceremony held on 31 January 1880 at the door of the Cathedral of San Marcos, Rear Admiral Lizardo Montero decorated and promoted Santos Mateo to Inspector de Guardias, a Civil Guard rank equivalent to that of Army Lieutenant at that time.

[9] The captured trophy remained in the church of that city, from where it was later transferred to that of Tacna, where it would later be found by Chilean troops some time later and returned to its regiment before the Lima campaign.

[11] After the end of the war he returned to Cuzco, where he married Julia Herrera, with whom he had children, living a peaceful life cultivating his family's land.

[1] On Monday, 31 December 2007, the Minister of the Interior, Luis Alva Castro, announced that the Hall of the Ambassadors of the Government Palace of Peru would bear the name of the national hero Mariano Santos Mateo.