The Aztecs were a Pre-Columbian Mesoamerican people of central Mexico in the 14th, 15th, and 16th centuries. They called themselves Mēxihcah (pronounced [meˈʃikaʔ]). The capital of the Aztec Empire was Tenochtitlan. During the empire, the city was built on a raised island in Lake Texcoco. Modern-day Mexico City was constructed on the ruins of Tenochtitlan. The Spanish colonization of the Americas reached the mainland during the reign of Hueyi Tlatoani Moctezuma II (Montezuma II). In 1521, Hernán Cortés, along with an allied army of other Native Americans, conquered the Aztecs through siege warfare, psychological warfare, direct combat, and the spread of disease. From 1375 until 1428, the Mexica were a tributary of Azcapotzalco. The Aztec rulers Acamapichtli, Huitzilihuitl and Chimalpopoca were, in fact, vassals of Tezozomoc, the Tepanec ruler of Azcapotzalco. When Tezozomoc died in 1421, his son Malazia ascended to the throne of Azcapotzalco. Maxtla (as Malazia was also known) sought to tighten Azcapotzalco's grip on the nearby city-states in the Valley of Mexico. In the process, Chimalpopoca, tlatoani of Tenochtitlan, was assassinated by Maxtla's agents while Nezahualcoyotl of Texcoco was forced into exile. Arrival in the Valley of Mexico In the Valley of Mexico (c. 1250 AD), there existed numerous city-states, including Chalco, Xochimilco, Tlacopan, Culhuacan, and Azcapotzalco. The most powerful were Culhuacan on the south shore of Lake Texcoco and Azcapotzalco on the west shore. As a result, when the Mexica arrived in the Valley of Mexico as a semi-nomadic tribe, they found most of the area already occupied. In roughly 1248, they first settled on Chapultepec, a hill on the west shore of Lake Texcoco, the site of numerous springs. In time, the Tepanecs of Azcapotzalco ousted the Mexica from Chapultepec and the ruler of Culhuacan, Cocoxtli, gave the Mexica permission to settle in the empty barrens of Tizaapan in 1299. There they married and assimilated into Culhuacan culture. In 1323, they asked the new ruler of Culhuacan, Achicometl, for his daughter, in order to make her the goddess Yaocihuatl. Unknown to the king, the Mexica actually planned to sacrifice her. The Mexica believed that by doing this the princess would join the gods as a deity. As the story goes, during a festival dinner, a priest came out wearing her flayed skin as part of the ritual. Upon seeing this, the king and the people of Culhuacan were horrified and expelled the Mexica. Forced to