There are three main hypotheses: Prison hypothesis: This theory suggests that the Spanish conqueror Garci González de Silva imprisoned Carib indigenous people in this area, leading to it being called "Calabozo," referring to a place of confinement.

Geographical hypothesis: It proposes that the Guárico River, as it curves around the plateau where the city is located, forms a large arch, similar to an old Spanish farming tool called "calabozo."

At the missionaries' request, on November 26, 1723, the governor granted permission to establish a Spanish town nearby, which was authorized by the bishop on December 15 of that year.

Local landowners obstructed the settlement for both the indigenous people and the Spanish settlers, but in 1726, the governor ordered the distribution of plots and allocated five leagues around the town for its inhabitants.

The council granted what was due to the town and to the missions of Santísima Trinidad and Nuestra Señora de los Ángeles on July 6, 1751, allocating one league around each.

On July 31, 1811, the city's council, in agreement with the Caracas Junta, proclaimed absolute independence, and on August 15, they welcomed the priest José Cortés de Madariaga, who returned from Bogotá after being sent by the government to sign a treaty of friendship, alliance, and federative union.

During the Venezuelan War of Independence, Calabozo became a focal point of military action in the plains, alternating control between republican and royalist forces.

The city was later captured by the Liberator, Simón Bolívar, who temporarily forced General Pablo Morillo to retreat following the battle of February 12, 1818.

Calabozo is situated in the midst of an extensive llano on the left bank of the Guárico River, on low ground, 325 feet above sea-level and 123 miles S.S.W.

The plain lies slightly above the level of intersecting rivers and is frequently flooded in the rainy season; in summer the heat is most oppressive, the average daily temperature being around 31 degrees Celsius.

The town is well built, regularly laid out with streets crossing at right angles, and possesses several fine old churches, a college and public school.

The abundance of water resources, such as rivers and reservoirs, supports irrigation and allows for maximizing crop productivity, both for local consumption and for export to other areas of Venezuela.

Rice thrives in anaerobic conditions, meaning it grows optimally in flooded soils, a factor supported by the efficient irrigation system available in the area.

This livestock activity has become a fundamental part of the local economy due to the abundance of natural resources that allow for the sector’s optimal development.