Beginning in 1598, the conflict primarily involved the Dutch companies and fleet invading Portuguese colonies in the Americas, Africa, and the East Indies.

However, the conflict had little to do with the war in Europe and served mainly as a way for the Dutch to gain an overseas empire and control trade at the cost of the Portuguese.

The Dutch Empire attacked many territories in Asia under the rule of the Portuguese and Spanish including Formosa, Ceylon, the Philippines, and commercial interests in Japan, Africa (Mina), and South America.

The Portuguese State of India, headquartered in Goa, was a network of key cities which controlled the maritime trade in the Indian Ocean: Sofala was the base for Portuguese operations in East Africa and was supported by Kilwa to better control the Mozambique Channel; from here, the routes took the trade to Goa which was the hub for the rest of the operations and where the India convoy ships out of Europe arrived; from Goa, going northwards, the trade would be protected by the North and Adventurers Fleets all the way to Daman and Diu which oversaw the northern trade and the Gulf of Cambay; while the Fleet of the North escorted merchant ships the Adventurers Fleet would also seek to disrupt the Mecca trade between northern India's Muslims and the Arabian Peninsula; the Diu fleet would then connect the trade to Hormuz which controlled the Persian Gulf routes and interrupted the Basra-Suez trade; southwards from Goa, the Cape Comorin fleet would escort the Goa merchants to Calicut and Cochin on the Malabar Coast and to Ceylon and the connection to the Bay of Bengal; in the Bay of Bengal, the most lucrative trade was on the Coromandel Coast where such settlements as São Tomé of Mylapore and Pulicat served as hubs; it was in the Coromandel and Ceylon settlements where the ships out of the Malacca route often laid anchor because they connected the Indian Ocean to the South China Sea; the Malacca fleet patrolled the Singapore Strait and the routes diverted to Celebes and what is now Indonesia at large in the south, and northwards to China and Japan; China provided silk and china to Macau from where the "Silver Carrack" connected to Japan where several products were exchanged for Japanese silver.

If both Diu and Hormuz would fall, that would prevent the West Asian markets from being taxed by Portugal, which would deny Lisbon the revenue from the southernmost course of the silk route.

The Portuguese had a century head start in the region and their empire allowed them access to converted and loyal local populations, which shored up inland, what naval power could not ensure at sea.

This put them safely distant from Goa but opportunistically close to Malacca and the sea lanes connecting the Pacific and Indian Oceans.

The Dutch blockade of Goa between 1604 and 1645 deprived Portuguese India from a safe connection to Lisbon – and Europe – for the remainder of the war.

The siege of Malacca of 1641, after many attempts, delivered the city to the Dutch and their regional allies (including the Sultanate of Johor), crucially breaking the spinal cord between Goa and the Orient.

[8] Amboina was captured from the Portuguese in 1605, but an attack on Malacca, the Battle of Cape Rachado, the following year narrowly failed in its objective to provide a more strategically located base in the East Indies with favorable monsoon winds.

For the next forty-four years, the two cities of Goa and Batavia would fight relentlessly, since they stood as the capital of Portuguese India and the VOC's base of operations.

Most of the fighting took place in west India, where the Dutch campaign in Malabar sought to replace the Portuguese monopoly on the spice trade.

After the fall of Qeshm and Hormuz to the Persians and English, the Portuguese struck out of their Muscat and Goa bases, which led to a destructive campaign against Persia's coastline and an alliance with Ottoman Basra.

[10] War between Philip's possessions and other countries led to a deterioration of the Portuguese Empire, as the loss of Hormuz to Persia, aided by England, but the Dutch Republic was the main beneficiary.

The 2 May 1654 action was a sea battle which took place near Colombo, Ceylon, when a force of 11 Dutch ships led by Rijckloff van Goens defeated 3 Portuguese galleons, which ran aground and were burnt near Carmona, north of Cabo de Rama.

In all, and also because the Dutch were kept busy with their expansion in Indonesia, the conquests made at the expense of the Portuguese were modest: some Indonesian possessions and a few cities and fortresses in South India.

The most important blow to the Portuguese eastern empire would be the conquest of Malacca in 1641 (depriving them of the control over these straits), Ceylon in 1658, and the Malabar Coast in 1663, even after the signing of the Treaty of The Hague in 1661.

In 1621, the Dutch West India Company (Geoctroyeerde Westindische Compagnie or GWC) was created to take control of the sugar trade and colonize America (the New Netherland project).

The Portuguese commander Matias de Albuquerque retreated his forces inland, to establish a camp dubbed Arraial do Bom Jesus.

[18] Until 1635, the Dutch were unable to harvest sugar due to Portuguese guerrilla attacks, and were virtually confined to the walled perimeter of the cities.

Nonetheless, by 1641, the Dutch captured São Luís, leaving them in control of northwestern Brazil between Maranhão and Sergipe in the south[20] John Maurice of Nassau was recalled from the governorship of New Holland in 1644 because of excessive expenditure and under suspicion of corruption.

In 1645, most of Dutch Brazil revolted under the leadership of mulatto landowner João Fernandes Vieira, who proclaimed himself loyal to the Portuguese Crown.

GWC forces were defeated at the Battle of Tabocas, virtually confining the Dutch to the fortified urban perimeters of coastal cities, defended by contingents of German and Flemish mercenaries.

In 1641, after a truce between Portugal and the Netherlands had been signed, the Dutch captured the island of São Tomé and before the end of 1642, the rest of Portuguese Gold Coast followed.

In August 1641, the Dutch formed a three-way alliance with the Kingdom of Kongo and Queen Nzinga of Ndongo, and with their assistance captured Luanda and Benguela, though without preventing the Portuguese from retreating inland into strongholds like Massangano, Ambaca, and Muxima.

Nonetheless, lacking firearms and artillery, Queen Nzinga and the Kongo proved unable to decisively defeat the Portuguese and their cannibalistic Imbangala allies.

Upon hearing of the fall of Luanda, Queen Nzinga retreated to Matamba, while the Dutch in São Tomé abandoned the island, which was reoccupied by the Portuguese later that year.

The Province of Zeeland had the most to gain from the return of the colony, but Johan de Witt, the Grand Pensionary of Holland, preferred a monetary compensation.

[24][25] In 1661, Portugal agreed to compensate the Dutch with eight million guilders and ceded the colonies of Ceylon (now Sri Lanka) and the Maluku Islands (part of present-day Indonesia).