The Chichimeca War (1550–90) was a military conflict between the Spanish Empire and the Chichimeca Confederation established in the territories today known as the Central Mexican Plateau, called by the Conquistadores La Gran Chichimeca. The epicenter of the hostilities was the region now called the Bajío. The Chichimeca War is recorded as the longest and most expensive military campaign confronting the Spanish Empire and indigenous people in Mesoamerica. The forty-year conflict was settled through several peace treaties driven by the Spaniards which led to the pacification and, ultimately, the streamlined integration of the native populations into the New Spain society.

The Chichimeca War (1550-1590) began eight years after the two-year Mixtón War. It can be considered a continuation of the rebellion as the fighting did not come to a halt in the intervening years. Unlike in the Mixtón rebellion, the Caxcanes were now allied with the Spanish. The war was fought in what are the present-day Mexican states of Zacatecas, Guanajuato, Aguascalientes, Jalisco, Queretaro, and San Luis Potosí.