They had complex trade networks and diplomacy methods. For example many tribes from the US southwest would only have diplomats be women or would have shared trade agreements rather than direct interaction. There is evidenence that free trade was really important to these people.

Some examples of some interactions are with Ramamuri, Talamanca, Tiwa, and more via trade. However, direct interactions tended to be mediated through specific peoples. Some examples include the cultures such as the Hohokam in Arizona and the Patayan in folowing the Colorado river which had strong ties with Mesoamerica. The Hohokam built ballcourts similar to those used in Mesoamerican ballgames even before the Aztecs develoepd their Confederacy and before their Imperial period. However, these relations carried over as other cultures took over and much as the Aztecs’ predecessors inherited their relations.

We know this because various tribes seemed to have spaces for diplomacy with Mesoamerican peoples. The sinagua pueblos had ballcourts for types of diplomacy rituals. We also know this from finding trade goods. Pueblo Indians tended to have materials from artifacts such as marine shells, macaw feathers, exotic pigments, and copper from Aztecs and also seemed to recieve goods from further south in Latin America that would trickle up such as materials from the Bribri tribes of Puerto Rico.