Sabana Grande (Spanish pronunciation: [saˈβana ˈɣɾande], Great Savannah) is a municipality of Puerto Rico located north of Lajas and Guánica; south of Maricao; east of San Germán; and west of Yauco. Sabana Grande is spread over seven wards and Sabana Grande Pueblo (The downtown area and the administrative center of the city). It is part of the San Germán-Cabo Rojo Metropolitan Statistical Area.

The municipality's name comes from the extensive plain that occupies the southern part of the municipality, better known as Sabana Grande Abajo. According to historian Mario Villar Roces, before 1808 there was a community with its own church on the land today known as Sabana Grande Arriba. Evidence of this is the oldest baptismal registry preserved from the area, as Sabana Grande was originally a sector of the municipality of San Germán.

Because the community was so far from the center of San Germán, residents felt a need to build a church, which was established as an auxiliary to the San Germán parish. The church was built and was devoted to San Isidro Labrador and Santa María de la Cabeza.

During Spanish rule, in order for a town to be established, the following had to take place: A group of vecinos ("neighbors" or citizens) that wanted to found a town had to grant a power of attorney to one or more other vecinos to represent them before the governor and viceroy. This person could authorize the founding of the town and the establishment of a parish. The grantors of the power of attorney had to be a majority in the given territory and more than ten in number. Once the case had been made, the governor appointed a "capitán poblador" or settlement official to represent the vecinos and one or more delegates, who usually lived in nearby cabildos, or hamlets. Proof was required that the settlement was so far from a church that it was very difficult for the settlers to partake of sacraments and municipal services. In general, proof was provided of the absence or bad condition of roads and bridges. If the petition was approved, it was required that the vecinos mark off the new municipality and build public works such as a church, a parish house, a government house (Casa del Rey), a slaughterhouse, and a cemetery, and to set aside land for the town square or plaza and the commons (ejidos). The vecinos were expected to cover the cost of building these works by levying special assessments. Usually one of the land owners donated some land for the founding. Once the requirements had been met, the governor authorized the founding of the town and the parish, and he appointed a Lieutenant at War who usually was the same capitán poblador.

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