In 1598, Dutch ships arrived at Aceh (northern Sumatra), marking an early phase of direct Dutch entry into Indian Ocean and Southeast Asian trade dominated by Portugal. These voyages aimed to break Portuguese control of key routes and commodities, especially spices. The arrival set the stage for a long, wide-ranging Dutch–Portuguese conflict fought through forts, naval actions, and alliances with local states.
In 1602, the Dutch Republic chartered the Dutch East India Company (VOC), giving it power to wage war, negotiate treaties, and build forts in Asia. This created a permanent, well-funded organization able to challenge Portuguese strongholds across the Indian Ocean. The VOC’s mix of trade and military force became the main Dutch tool in the conflict.
On 1605-02-22, VOC forces under Steven van der Hagen captured the Portuguese fort on Ambon (Amboina) and renamed it Fort Victoria. Taking Ambon helped the Dutch secure a base in the clove-producing Moluccas and weakened Portugal’s ability to police spice shipping lanes. It also showed how fort seizures could quickly shift control of regional trade.
In 1638–1639, the VOC tried to blockade and possibly capture Goa, the main center of Portuguese power in India. Portuguese forces fought off the Dutch fleets in a series of engagements known as the Battle of Goa. The outcome demonstrated that Portugal could still defend key ports, even as Dutch pressure grew elsewhere.
On 1638-05-18, Dutch forces captured the Portuguese fort at Batticaloa, an early victory in the campaign to remove Portugal from Sri Lanka’s coasts. Control of such forts mattered because they protected harbors and helped enforce trade monopolies, including cinnamon. The fall of Batticaloa signaled that the new Dutch–Kandy partnership could take fortified Portuguese positions.
On 1638-05-23, the VOC and the Kingdom of Kandy (in Sri Lanka) signed a military and trade treaty aimed at expelling the Portuguese from coastal forts. The agreement linked Dutch naval power with local land forces, creating a practical coalition against Portuguese Ceylon. Differences between language versions of the treaty later fueled disputes, but the alliance initially drove rapid Dutch gains.
From 1638-03-08 to 1638-03-13, the VOC and Kandyan allies besieged and captured the Portuguese fort at Galle. Galle mattered because it helped control access to southern Sri Lanka and the cinnamon-producing districts linked to the port. After this, Galle served for years as a main Dutch power center on the island while pressure on Colombo continued.
From 1640-08-03 to 1641-01-14, the VOC and the Johor Sultanate besieged Portuguese Malacca and forced its surrender. Malacca controlled the narrow Strait of Malacca, a critical chokepoint for Indian Ocean–Southeast Asia shipping. The Dutch victory removed a major Portuguese fortress from the region and strengthened Dutch control of maritime trade routes.
On 1656-05-12, the VOC captured Colombo after a prolonged siege, taking the main Portuguese administrative and military center in Sri Lanka. This shifted the balance of power on the island by cutting off Portuguese coordination and resupply. The fall of Colombo also enabled Dutch forces to move against remaining Portuguese forts in the north.
On 1658-02-22, Dutch forces captured Mannar, an important fort and island position near the northern approaches to Sri Lanka. This victory helped isolate the remaining Portuguese strongholds and opened the way to the final campaign at Jaffna. By this stage, Portuguese coastal power in Sri Lanka was collapsing under coordinated Dutch sea control and land operations.
In June 1658, the Dutch captured Jaffna, completing the removal of Portuguese rule from Sri Lanka after more than a century of presence. With the loss of Jaffna and earlier defeats at Colombo and Mannar, Portugal no longer controlled major Sri Lankan forts. The Dutch then reorganized coastal territories under VOC administration, shaping the island’s trade and fort network for decades.
On 1661-08-06, the Dutch Republic and Portugal signed the Treaty of The Hague, a major diplomatic step toward ending the long war between them. The treaty recognized Portuguese sovereignty over Dutch Brazil in exchange for a large indemnity, reflecting how global pressures shaped negotiations. Even after this agreement, fighting and takeovers in parts of the Indian Ocean world continued for a short time as campaigns already underway reached their conclusions.
On 1663-01-08, the Portuguese garrison at Cochin (Kochi) capitulated after a Dutch siege, ending a key Portuguese position on India’s Malabar Coast. This marked a decisive outcome of the late-stage Dutch campaign to remove Portuguese forts that supported Indian Ocean shipping and pepper trade. Cochin then became a major Dutch base in southwest India, reinforcing the new regional balance of power after decades of conflict.
Dutch–Portuguese conflicts in the Indian Ocean (1598–1663)