There are some sparse records that exist regarding courtship and marriage in Aztec society. A notable one being folio 61 of the Codex Mendoza which depicts a wedding scene. From what is known, it appears that in those days, the parents of an eligible bachelor would solicit the help of a matchmaker to find a prospective wife for their son (usually at around the age of 20). The matchmaker would put the two families in contact, after which point, if the marriage was deemed favorable by the community, the parents of the groom would provide a dowry-like offering to the parents of the bride. If they accepted, the marriage process would begin. Someone who was knowledgeable in the Count of Days would select a favorable date on which the wedding would be held. On the day of the wedding, the families and other people who were invited would gather together to feast, drink, and celebrate, however the wedding procession itself would start at night, as the bride would be carried in by the matchmaker. It seems this particular tradition was also practiced by the Mixtecs, and can also be observed on Folio 19 of the Codex Zouche-Nuttall. For the ceremony, the bride and groom would be seated together on a reed mat. The mother of the groom would provide the bride with a new Huipil (blouse) and skirt, and the mother of the bride would provide the groom with a new cape and loincloth. The matchmaker would then tie the bride's huipil and the groom's cape into a knot, symbolizing their new union, and they would be escorted to a bedchamber where they would remain in privacy for four days. At the end of the four days of privacy, they would be ready to join adult society as a married couple.

Follow-up question: what did courtship & marriage look like for the Inca?