Final answer:
The empire in Mesoamerica between 800 and 1000, around the time when the Maya civilization was declining, was the Toltecs.
Step-by-step explanation:
The empire in Mesoamerica between 800 and 1000, around the time when the Maya civilization was declining, was the Toltecs. The Toltecs were an ancient civilization known for their military prowess and cultural influence on the region.
Learn more about Mesoamerican empires during the decline of the Maya civilization