Question: What people group established an empire in the valley of mexico?
Disambiguated questions and answers: question: What people group established an empire in the valley of mexico in the 10th century?
What people group established an empire in the valley of mexico in 1325?
answer: the Toltec
Toltec
the Aztec
Aztec
Natural Questions answer: The Aztec (from the Wikipedia article "History of Mexico")