Marcos was born in Nice, France (then under the control of the Italian Savoy Family) in 1495. As he grew up, he became a member of the Franciscan Order of Friars and became involved with the Sete Cidades. By the time he arrived in Central America in 1531, he was secretly a High Priest of the Sete Cidades.
In America, he engaged in preaching missions to convert local populations to Christianity, while searching the evidence of the Seven Patriarchs and the Seven Cities of Gold, accompanied by his guide, Esteban the Moor. On one such mission, in 1597, Marcos, Esteban, and a group of Spanish Conquistadors discovered the ruins of Quivira, which Marcos initially believed to be one of the Seven Cities due to confusing the Seven Gods of Quiviran Culture with the Sign of the Seven Fathers. However, once he witnessed the remains of the Quivirans, he became convinced that Quivira is a place of evil and the devil, so he sacrificed Esteban to seal the gates of hell according to the rituals of the Sete Cidades. The Conquistadors, however, did not share Marcos' concerns about Quivira and planned to return to loot it and mine gold from the Golden Abyss. To prevent them from revealing its location, Marcos murdered them all with poison. Upon returning to Northern Mexico, Marcos engraved a map to Quivira on Esteban's sword and placed it within Esteban's tomb at the Chamber of the Seven Fathers to save his guide's soul.
In order to further conceal Quivira's location, Marcos led Francisco Váquez de Coronado, the provincial governor, on an expedition to find it. The expedition headed north, instead of south. Instead of finding Quivira, they discovered only the villages of Native Americans. This led to Coronado branding Marcos as the 'liar friar'.
Friar Marcos de Niza's journey through la Selva de las Serpientes can be documented through his twelve artifacts.
Extracts from his Journal
Several extracts from Marcos' personal journal appear during Golden Abyss.
'We sacrifice these souls in the name of the Holy Spirit. The Sword of Stephen shall bear witness to their crimes in the Chamber of the Seven Fathers.'
'In the year of Our Lord 1537, we came upon the sign of seven, the doorway to eternity, as we thought, but to our dismay learned it's not the door to heaven, but to hell. All was death and we fled. The captain and his men seeing only gold, and not the mortal peril of their souls, vowed a solemn oath to return, their blasphemy...'
'...under threat of ex-communication. In the dark of night...'
'...that they might lose their lives to save their souls. The Temple of the Serpent guards the pathway to hell. The Sword of Stephen, like the flaming sword of Uriel, guards its entrance for eternity. Our sacrifice shall remain within these walls forever. Signed, Friar Marcos de Niza.'
- Marcos was the first person to report the Seven Cities of Cíbola in recorded history, and may have used it as an alternate name for Quivira in his report to Coronado. Coronado, as many Conquistadors did, expected to find gold, even though Marcos' report made no mention of it.