Its territory roughly covered the geographic area of the present-day Mexican state of Michoacán, as well as parts of Guanajuato, Guerrero, and Jalisco.

The empire included different groups, primarily Purépecha people and additionally Matlazincas and Mazahuas in the east, Chichimecs such as Otomíes and Tecuexes in the Bajio, Cocas around Lake Chapala, Chontales de Guerrero/Tuxtecos around the Balsas River valley, Chumbios around Zacatula, and Nahuas both on the Pacific coast and in the heartland.

Early lithic evidence from before 2500 BC, like fluted points and stone utensils are found at some megafauna kill sites.

[citation needed] In the late classic, at least two non-Purépecha ethnic groups lived around Lake Pátzcuaro: Nahuatl speakers in Jarácuaro, and some Chichimecan cultures on the northern banks, with the Nahua population being the second largest.

According to the Relación de Michoacán a visionary leader of the Purépecha named Tariácuri decided to gather the communities around Lake Pátzcuaro into one strong state.

Around 1300 he undertook the first conquests and installed his sons Hiripan and Tangáxuan as lords of Ihuatzio and Tzintzuntzan respectively, himself ruling from Pátzcuari city.

Under the rule of cazonci Tzitzipandáquare a number of regions were conquered, only to be lost again by rebellions or strategic retreats when confronted with Aztec expansion.

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 Purepecha lands.

He supported attacks on Purepecha lands by other ethnic groups allied with or subjugated to the Aztecs such as Matlatzincas, Chontales, and Cuitlatecs.

Between 1480 and 1510, the Iréchikwa occupied parts of present day Colima and Jalisco in order to secure Nitratine (Chile saltpeter) mines in the region.

Throughout the occupation, the peoples of Colima, Sayula, Zapotlán, Tapalpa, and Autlán resisted Purepecha rule in the Saltpeter War.

[10] Historian Robert West states, "The Tarascans and their neighbors near the Pacific coast were the foremost metallurgists of pre-Conquest Mexico."

Copper-silver alloy artefacts found in the palaces and graves of Tzintzuntzan include rodelas, armlets, bracelets and cups.

This resulted in a strange arrangement where both Cortés and Tangáxuan considered themselves rulers of Michoacán for the following years: the population of the area paid tribute to them both.

When the Spanish found out that Tangáxuan was still de facto ruler of his empire but only supplied the Spanish with a small part of the resources extracted from the population they sent the ruthless conquistador Nuño de Guzmán, who allied himself with a Purepecha noble Don Pedro Panza Cuinierángari, and the cazonci was executed on February 14, 1530.