State of Mexico

The State of Mexico, officially just Mexico, is one of the 32 federal entities of the United Mexican States. Colloquially, it is known as Edomex ([e.ðoˈmeks], from Edo. & México) to distinguish it from the name of the country. It is the most populous and second most densely populated state in Mexico.

Located in central Mexico, the state is divided into 125 municipalities. The state capital city is Toluca de Lerdo ("Toluca"), while its largest city is Ecatepec de Morelos ("Ecatepec"). The State of Mexico surrounds Mexico City on three sides. It borders the states of Querétaro and Hidalgo to the north, Morelos and Guerrero to the south, Michoacán to the west, and Tlaxcala and Puebla to the east.

The territory now comprising the State of Mexico once formed the core of the pre-Hispanic Aztec Empire. During the Spanish colonial period, the region was incorporated into New Spain. After gaining independence in the 19th century, Mexico City was chosen as the new nation's capital; its territory was separated from the state. Years later, parts of the state were broken off to form the states of Hidalgo, Guerrero, and Morelos. These territorial separations have left the state with the size and shape it has today, with the Toluca Valley to the west of Mexico City and a panhandle that extends around the north and east of this entity.

The demonym used to refer to people and things from the state is mexiquense, distinct from mexicano ('Mexican'), which describes the people or things from the whole country.