Today, more than 7 million of Mexico’s 126 million people speak 364 Indian linguistic variants (dialects), but almost 90% of those people are bilingual, speaking both Spanish and an Indigenous language. Those who do not speak Spanish are called monolingual.

Oaxaca is characterized by extreme geographic fragmentation with extensive mountain systems, wide tropical coastal plains and fertile valleys. The entire state is very mountainous, being crossed by three cordilleras:

1. The Sierra Madre Oriental in western Oaxaca.

2. The Sierra Madre del Sur covers 70% of the state territory.

3. The Sierra Atravesada in the region of the Isthmus of Tehuantepec.

Most Americans have heard of Oaxaca and its copious diversity. Usually this knowledge is spread by word of mouth or through informative newspaper and magazine articles. However, Mexico’s census Mexico’s Census Agency — the Instituto Nacional de Estadística y Geografía (INEGI) — known to Americans as the National Institute of Statistics and Geography — is the original source for much of the census data regarding Indigenous Mexican languages today. And this information will be outlined below.

The State of Oaxaca is located in the south of Mexico where the Eastern Sierra Madre and the Southern Sierra Madre mountain ranges merge. Oaxaca shares common borders with Guerrero (on the west), Puebla (on the north), Veracruz (on the north and northeast), and Chiapas (on the east). Oaxaca also shares a long coastline with the Pacific Ocean on its south.