to recent excavations. This site has a history of at least 3500 years with Olmec and Chiapas-origin figures found in its oldest sections. This and the abundance of marine shells indicate that this site in the Cañada de Tehuantepec was the main axis of communication between the Oaxacan highlands the Isthmus of Tehuantepec and into Guatemala since early in Mesoamerican history. The Zapotec kingdom of Zaachila expanded into the Tehuantepec area under Cosijoeza starting in 1487, pushing the native Huaves to the narrow coastal strips around the Tehuantepec lagoons. With this, the Zapotecs gained control of the salt deposits of the area, which was a valuable commodity. Tehuantepec became a second Zapotec capital. This dominion had relations with the Aztecs but did not pay tribute and controlled the trade route to Central America. The influence of this dominion extended west to Nexapa and along the coast to Tlapanatepec. Tequixixtlan and Xallapan were subordinate dominions, ruled by governors sent from Tehuantepec. Tehuantepec increased in importance as the original capital of Zaachila came under pressure from the Mixtecs and later from the Aztecs by the end of the 15th century. The Aztecs’ interest here was the control the trade route between the Mexican Plateau to Soconusco in Chiapas and into Guatemala. The Aztecs attacked Tehuantepec in 1496, and it was defended by an alliance of Mixtecs and Zapotecs. These two groups normally fought each other, but allied in the face of the foreign threat. This and the city's formidable defenses led to a seven-month siege under Aztec ruler Axayacatl. The next Aztec chief Ahuiztotl, decided to marry his daughter Coyolicatzin to the Zapotec king Cosijoeza. This ended the war. At the time of the Conquest and for some time after, the area was dominated by three linguistic groups, Zapotec, Mixe and Chontal, which are unrelated. The Zapotecs occupied the area from the Sierra Madre del Sur and Xallapan up to Tehuantepec. The Chontales were found between Mazatlán and Tequixixtlan. The Mixes occupied the high mountain areas, centered in Utlatepec. Cosijoeza's son Cosijopii became the ruler of Tehuantepec shortly before the arrival of the Spanish in 1518. Pedro de Alvarado made two incursions from the west in 1522 arriving to the Mixe area of Ultatepec and Xoconochco. Alvarado entered Tehuantepec again in 1524, subduing the local population in Tequixixtlan and Xallapan. However, many years passed before the Spanish had full control of the