524 ANNUAL REPORT SMITHSONIAN INSTITUTION, 19 3 8 



At the close of the fourteenth century the Tepanec succeeded in 

 overthrowing the Texcocans, but their sway was short-lived. In the 

 second quarter of the fifteenth century, the deposed ruler of Texcoco 

 raised a revolt, and enlisting the services of the Tenochcas or Mexico 

 City Aztecs and the Tacubans, destroyed forever the political power 

 of Azcapotzalco. These three city-states then assumed the leader- 

 ship of the valley and by a series of conquests enlarged their power to 

 cover great sections of southern and eastern Mexico. Gradually the 

 Aztecs supplanted the Texcocans as the dominant political power in 

 the league, but the cultural and intellectual leadership still remained 

 with Texcoco. At the time of the Conquest the Aztec dominion was 

 at its height, but the disaster in store for it at Spanish hands was but 

 an acceleration of the seething hatred felt by the subject people who 

 allied themselves speedily with the white invaders. 



This history, culled from documentary sources, resolves itself into 

 several stages or periods: 



(1) The legendary period of the foundation of the world. 



(2) The Toltec Empire. 



(3) The Chichimec period. 



(4) The formation of the Texcocan kingdom. 



(5) The rise of the Aztec Empire. 



We must now see how this pattern compares with the sequence of 

 cultures, derived by excavation. This latter process has been a 

 long one, lasting over 25 years, and still is not complete. While the 

 Department of Monuments of Mexico and the American Museum of 

 Natural History have been most active, yeoman service has been 

 done by the now-disbanded International School, the Stockholm 

 Museum, and the University of Arizona. Now the point has been 

 reached where a correlation can be made between the tribes of the 

 valley and their material culture. 



Traces are found of five main culture levels, differing from each 

 other in the form and decoration of their pottery, in the artistic 

 styles of their stone and clay sculptures, and in their architecture. 

 Through the study of the strata in the rubbish heaps, minor time 

 stages can be distinguished within each culture group. 



The earliest traces of man were originally found beneath a lava 

 flow at the south of Mexico, but careful stratigraphical analysis of 

 rubbish heaps in the Guadalupe hills, northeast of Mexico City, 

 where similar material was found, revealed a long history for these 

 finds, which resolved themselves into the handiwork of two peoples. 

 The earlier culture, named Copilco-Zacatenco, after the sites where 

 first found, showed five stages of development, represented in 20-foot 

 accumulations of refuse indicative of a long lapse of time. The general 

 culture level was on a par with that of the more developed of our 

 North American Indian tribes. The later finds, called Cuicuilco- 



