It's stil debated if Viceroy Mendoza, who purchased Esteban from his Spanish slave owner Andrés Dorantes, was free or still a slave when he led Friar Marcos's expedition to find the "Seven Cities of Cíblola."
Sometime in the months after the arrival in Mexico City of Esteban and his three Spanish companions in the late summer of 1536, Viceroy Antonio de Mendoza bought Esteban. Mendoza was the king's representative in New Spain, now known as Mexico. Mendoza wrote to King Carlos I, who also ruled as Holy Roman Emperor Carlos V (the ruler's name is almost always Anglicized to Charles in English books), that he tried unsuccessfully his first time at purchasing Esteban. The viceroy presented Dorantes with a silver plate heaped with 500 pesos, which was about five times the typical price for a slave in those days. But Dorantes said he couldn't bare to part with his personal slave.
But under whatever persuasion from the most powerful man in Mexico, Dorantes relinquished Esteban to Mendoza, saying his generosity was for the greater glory of the king and emperor.
Some have interpreted Dorantes's refusal to sell Esteban as indicating a sentimental attachment between master and slave. But researcher Robert Goodwin concluded there was a more prosaic reason. Dorantes knew that Mendoza planned to use Esteban as a guide to the Seven Cities. "As long as Esteban remained his property," Goodwin wrote, "Dorantes could stake his own claim to any riches his slave might discover."
In describing the transaction, Mendoza created a precedent in referring to an African slave by name to Spain's king. On December 10, 1537, he wrote to the king: "I purchased from Dorantes a Black named Esteban for this purpose (exploring to the north)."
Records are vague about whether Esteban remained a slave lent by Dorantes, or was a slave now owned by Mendoza, or whether the viceroy emancipated Esteban. A hint is in the fact that Mendoza and everyone else never again referred to the African by his slave nickname of Estevanico -- always referring to him as Esteban de Dorantes or as just Esteban. Also, as historian Hsain Ilahiane noted, "Esteban's free acts and resistance (toward Friar Marcos)...suggest that he held the status of (the viceroy's) employee."