at the time of the spanish conquest the southern part of the toluca valley, including the tenango area, was dominated ethnically by the matlatzincas, whose center was the teotenango site on tetepetl hill. however, this city had been conquered around 1474 by axayacatl and was part of the aztec empire, so it was politically dominated by the aztecs. spanish takeover of the southern toluca valley was accomplished by andres de tapia, with support of gonzalo de sandoval from toluca. however, due to the teutenango treaty of 1582, credit for the conquest is given to martin dorantes.