There are no authentic documents in existence explaining the original stock of the Mangyan people, but later theoreticians postulate that they migrated from Indonesia before 775 A.D.

By 779, the southwest coast of the island was already a known trading center, and its fine natural harbor frequented by Arab, Indian and Chinese maritime traders who plied the route.

Internal trouble in the Chinese home front, however, recalled the armada, and the attempts of the empire to annex the archipelago did not materialize.

- Orang Dampuans (economic refugees from Sulu) crossed Mindoro Strait from Paragua (now Palawan) and settled along the coastal areas, developing progressive maritime communities.

In 1572, Captain Juan de Salcedo of the Spanish expeditionary army set sail from Cebu and explored the west coast of the island, encountering the Mangyans, who appeared used to seeing foreigners and were not at all a bit surprised at their arrival.

On the contrary, it was Salcedo and Martin de Goiti who were surprised to see cross designs on the clothing and basketwork of the natives, and thought some early Christian missionary had been there before them.

The Spaniards also encountered Moro settlers in Lubang Island that were vassals of and paid tribute to the kingdom of Maynila in the North, under Rajah Sulayman.

The Moros, who apparently had heard of the invaders from their kinsmen in the south, engaged the small Spanish force who landed on their shore, but the Spaniards' arquebuses and cannon fire from the ships hoved-to broadside to the island took the field.

In 1757, the Moros, more particularly, the Iranuns (a relative of the Maranaws of the Lake Lanao regions) organized a war fleet of 74 fast native ships called prahus.

The fact that a Moro fort at Mamburao threatened Manila, the capital of the colonial government, embarrassed the conquerors in the eyes of their native subjects, which was politically intolerable to the Spanish administrators.

It was not until the commission of the vapor, fast steamships, in the mid-18th century that the Spanish navy successfully patrolled the archipelagic waters, and fared well against the wind-powered native seacraft of the pirates.

With losses to the Spanish navy increasing, and the eventual fall in profits from slave selling, raiding became less appealing to the Iranuns and their Islamic supporters.

The pirate fort in Mamburao was abandoned, and the Moros retreated to Mindanao to consolidate their forces and continue the Moslem resistance at the homefront.

In 1897, the Spaniards posted a rifle company of 140 troops and 51 marines to Calapan to secure the island from the forces of General Emilio Aguinaldo and his revolutionary army, then beginning to overrun Spanish positions in the archipelago.

It was only the arrival of 1,000 regular army troops with artillery, all under the command of General Malvar in Batangas, that compelled the surrender of the Spaniards under Governor Morales.

A new battalion "Mindoro", with two rifle companies, was formed under the command of Captain Ruperto Hernandez and Estanislao Cayton, both from Batangas.

In 1910, the successor United States politico-military administration granted over 50 square kilometres (19 sq mi) of land to the Welch and Fargo Sugar Company in what is now San Jose, which built the first modern and biggest sugar mill in the Far East at Siete Central (now barangay Central).

In the same year, the boldly developing community of sugar cane planters, mill workers, company professionals and businessmen enabled the creation of San Jose as an official Philippine town.

In April 2023, the provincial government placed the entire province under a state of calamity due to the 20-hour daily power outage that has been occurring for a month and a half.

General land surface features that characterize Occidental Mindoro are mountains, rivers, hills, valleys, wide plains and some small fresh water lakes.

Significant hilly areas can be found rolling off in Santa Cruz in the north, and in San Jose and Magsaysay in the south.

Rains begin to fall in the province in late May, intensifying through June, July, August, September and October, then gradually subsides in November.

[citation needed] On the other hand, dry season starts in November, with rainfall subsiding in intensity, and altogether ceasing in January, February, March and April.

March and April are the driest period, with cloudless skies and parched earth characterizing the general area.

Tobacco, onions, garlic and vegetables are grown during the dry season (November to May) since they are not water-intensive crops, and require longer photoperiodicity.

Rice, corn, onions, garlic, salt, fishes (both wild and cultured) are some of the relatively significant surpluses produced in the province in exportable quantities.

Mangoes, cashew nuts, cooking bananas (saba) and some other fruits grown in upland orchards are among the other exports of Occidental Mindoro that have traditionally contributed to its income.

A study concluded that from 1997 to 2003, the cost of production rose by 47 per cent, while the income derived from marketing rice maintained 1997 levels.