The first inhabitants of the peninsula came from Asia through the Bering Strait, some 14 thousand years ago. from them, descended the indigenous groups: kiliwas, pai pai and cucapás, which together are called the yumana family.
In 1533, Fortún Jiménez at the service of Hernán Cortés is the first European to set foot on the peninsula. Later expeditions headed by Cortés continued with arrivals of Francisco Ulloa in 1539, Juan Rodriguez Cabrillo in 1542 and Sebastián Vizcaíno in 1596; these facts would be fundamental to set boundaries and letters navigation of the peninsula that before these explorations was considered an island.
In 1602 early attempts would commence to populate and evangelize the territory, first in charge of Franciscan priests as fray Antonio Ascension and several decades later with Jesuits as Francisco Eusebius Kino, who would come in 1683, and Juan María Salvatierra, which would fo low in 1697. To the expulsion of the Jesuits in 1767, Franciscan priests, headed by fray Junípero Serra, continued the evangelization feat as far north as the Napa Valley in the United States region which was called Alta California, differentiating this from the Peninsula.
In 1772 to 1833, the Dominicans would end the cycle of the missionary stage in the State of Baja California.
After the independence of Mexico in 1821, the province of Baja California remained isolated from the rest of Mexico and virtually uninhabited except for some small populations. In 1846 as a result of the American invasion, Mexico would lose almost half of its territory, so that high California (California today) would be part of the United States. In 1887 by Porfirio Díaz Decree, Baja California would be divided into two districts: North and South.
It was until 1936, 15 years after the Mexican Revolution and thanks in large part to the Decree of President Lázaro Cárdenas, promoter of populating the area and generating new of sources of production, which the State of Baja California, then known as Territory of the Baja California Norte; would give launch to a genuine period of integration with the rest of the country. From 1910 to 1950, its population grew 50 times, by registering that year 520,165 inhabitants. During this time the State received thousands of immigrants from all of Mexico, Germany, France and China.
Two years later, in 1952, the territory would be elevated to state of Baja California level, creating in turn Mexicali, Tijuana, Ensenada and Tecate municipalities.
In 1995, Rosarito Beach become the fifth municipality, since then no change has occurred in the political division of the State.