The Aztec people were certain ethnic groups of central Mexico, particularly those groups who spoke the Nahuatl language and who dominated large parts of Mesoamerica from the 14th to 16th centuries. With the decline of the Toltec civilization came political fragmentation in the Valley of Mexico, and into this new game of political contenders for the Toltec throne stepped outsiders: the Aztec. Newcomers to the Valley of Mexico, they were seen as crude and unrefined in the eyes of the existing Mesoamerican civilizations, such as the fallen Toltec empire. Latecomers to Mexico's central plateau, the Aztecs thought of themselves as heirs to the prestigious civilizations that had preceded them, much as Charlemagne did with respect to the fallen Roman Empire.