a person's name (Coatl with the -tzin reverential); e.g. a famous Nahua interpreter active in the migration of ancestors from Chicomoztoc to Cholula and final settlement in Quauhtinchan (today: Cuauhtinchan) (sixteenth century, Quauhtinchan)
There was a Coatzin who was a "nahuatlato," or Nahuatl-speaking interpreter. He is mentioned several times in the Historia Tolteca Chichimeca. In one place, we learn that he was a Xilotzinca. (sixteenth century, Quauhtinchan)
Coatzin, the nahuatlato (interpreter), also appears in the Mapa de Cuauhtinchan No. 2, a sixteenth-century pictorial, bark-paper manuscript covering much of the same history as the Historia Tolteca Chichimeca. (sixteenth century, Quauhtinchan)
Coatzin's role as an interpreter (as described in the Historia Tolteca-Chichimeca) tells us that the Tolteca spoke one language and the Chichimeca spoke another. His role was therefore a "crucial diplomatic" one in the negotiations.
Niman ya yc ualquiza y nauatlato yn couatzin niman ya uallatoua qui[lh]uia yn icxicouatl yn quetzalteueyac ac ameuan campa auitze = Luego ya sale Couatzin, intérprete del nauatl, ya habla; le dice a Icxicouatl y a Quetzalteueyac:
Quiénes son ustedes? De donde vienen? (Quauhtinchan, s. XVI)