 In the 1470s Aztecs under Axayacatl captured a series of Tarascan frontier towns and closed in on the Tarascan heartland, but were eventually defeated.This experience prompted the Tarascan ruler to further fortify the Aztec frontier with military centers along the border, such as at Cutzamala.He also allowed Otomies and Matlatzincas who had been driven out of their homelands by the Aztecs to settle in the border area under the condition that they took part in the defense of the Tarascan lands.