The Aztec word macehualtin designated the people that did not belong to the upper social spheres (artisans, traders, and government officials), but excluded the sphere of the slaves. The word is derived from the verb macehualo, which means “work to earn”, or “work to deserve”. In modern nahuatl, the word has a pejorative meaning, but in the early Aztec times, the word did not have such context. There are various examples in Aztec literature in which the word macehualtin can be translated only as “people”, without any despise. At some point in history, the social conception was formed that the macehualli ignored the good manners. Macehualtoa means “to speak in a primitive way”, and macehualtic can be translated as “vulgar”.

The Mexican macehualli, member of a calpulli in the city of Tenochtitlan had the right to use a piece of land to build a house for his family and to cultivate his crops. His children were admitted in the local schools, and he could take part in the election of the local chiefs, though in the last instance, their final designation was carried out by the emperor. But, as he is still a plebeian, he is subject to heavy duties. In particular, to those duties that relate to the military and public services. The macehualli could be called at any moment to carry out cleaning duties in the streets. They were also called to supply the workforce for the conservation and construction of public roads and bridges. If the palace needed wood or water, a platoon of macehualli was sent in order to carry out the duty.

The Aztec macehualli belonged to a privileged social class when compared to the macehualli of a conquered city, or in comparison to the rural worker. The macehualli paid his taxes, but very similar to the Roman anona, he was also recipient of those taxes paid by the Aztec provinces to the city of Tenochtitlan.

Regarding the opportunities for climbing the social ladder, they were relatively open. The military career and the religious service provided the macehualli of several opportunities. There were also the cases where the favor of a noble lord transformed the life of a macehualli. Such is the case of “Xochitlacotzin”, a gardener who had the courage to make a claim to the emperor Moctezuma II, who was impressed by his honesty and therefore made him a member of his court.

At the bottom of the “free” social classes were the peasants without land, or tlamaitl. Usually victims of wars or civil strikes, they were forced to offer their services to noble lords. In exchange of their services, the noble Aztec lord provided the peasant and his family of shelter and food.

The lowest social class among the Aztecs was occupied by the tlacotlin. There isn't a proper English term that defines this condition, but is comes close to being a slave. Motolinia, a Franciscan missionary of the XVIth century, described that the Aztec tolacoltin had many benefits when compared to the European condition of slaves. When the Spanish conquerors introduced in Mexico slavery in the European fashion, and many of the native Mexicans were marked like cattle in the face, and were treated harsher than animals, many of those slaves wished for the luck of the Aztec tlacoltin.

What were then the conditions of the Aztecs slaves? First of all, the tlacoltin worked for someone else, usually like an agricultural or domestic worker. The tlacotli did not receive any payment for his services, but he is given shelter, food and clothes like an ordinary citizen. There were the cases of tlacoltin that became the “butlers” of big houses and had under their command free people. Besides this, the tlacoltin could accumulate goods and wealth, and if he had enough, he could also purchase houses, land and even slaves for his own service. An Aztec slave could marry a free woman; often, an Aztec widow married one of her slaves who later became the lord of the house and the chief of the family. Their children were all born free, since there wasn't any adhered hereditary stigma to the Aztec condition of slave. One of the greatest Aztec emperors, Itzcóatl was the son of Acamapichtli and a slave.

Towards the end of the XVIth century, the number of tlacoltin appeared to be rising. The development of trade with distant territories, tributes and such diversity in lifestyles explain this. In a complex, rapidly changing society, the rise of some people gave as a consequence the fall of others. There was still, however, hope even at the bottom of social Aztec condition.