Answer
The Chichimecas, nomadic groups inhabiting northern Mexico, engaged in conflicts with the mighty Aztec Empire. The Chichimecas resisted Aztec expansion and control, leading to frequent clashes and battles between the two entities. These conflicts were primarily fueled by territorial disputes and the desire for resources, as the Chichimecas sought to maintain their autonomy and way of life in the face of Aztec encroachment.