On 17 March 1824, representatives of Britain and the Netherlands signed a treaty in London consisting of 17 articles. The agreement effectively drew a dividing line along the Strait of Malacca. It was ratified by Britain on 30 April 1824 and by the Netherlands on 2 June 1824. The ratifications were exchanged in London on 8 June 1824.
The treaty was essentially a territorial exchange between the two colonial powers. Britain ceded Bencoolen in Sumatra, while the Netherlands ceded Malacca on the Malay Peninsula.
However, the greatest consequence fell upon those who had no seat at the negotiating table. The Johor–Riau–Lingga–Pahang Sultanate, a Malay kingdom whose territory stretched across both sides of the strait, was divided into two without the knowledge of its sultan or nobility.
Nearly two centuries later, the same dividing line can still be traced on the political map of Southeast Asia. It became the foundation of the present-day Indonesia–Malaysia border and part of the Indonesia–Singapore border.
A Dispute Inherited from the Napoleonic Wars
The 1824 treaty grew out of an unresolved dispute following the Anglo-Dutch Treaty of 1814. That post-Napoleonic agreement restored Dutch colonies that Britain had occupied during the wars.
However, the territorial boundaries defined in the 1814 treaty were ambiguous. Those ambiguities created new tensions as both countries resumed their commercial activities in the Malay Archipelago.
The dispute reached its peak after Thomas Stamford Raffles, a British representative of the East India Company, established a trading post in Singapore in 1819 without Dutch approval. At the time, the island was considered part of the Dutch sphere of influence through the Johor Sultanate.
Over the next five years, London and The Hague negotiated to resolve these territorial and commercial disputes comprehensively.
A Territorial Exchange in London
The negotiations resulted in a treaty that divided territories and established commercial rules between Britain and the Netherlands in India, the Malay Peninsula, and the Malay Archipelago.
Britain ceded Bencoolen (Fort Marlborough), along with all of its possessions in Sumatra, to the Netherlands. It also agreed not to establish new trading posts or conclude treaties with local rulers on the island.
In return, the Netherlands transferred the town and fortress of Malacca to Britain. It likewise agreed not to establish new trading posts on the Malay Peninsula. The Netherlands also withdrew its objections to the British occupation of Singapore, while Britain withdrew its objections to the Dutch occupation of Billiton Island.
The treaty also theoretically brought an end to more than two centuries of Dutch trade monopoly in the Malay Archipelago. The only exception was the Maluku Islands, which remained exempt so that the Dutch could preserve their spice monopoly.
One Sultanate, Two Sultans
The treaty's dividing line followed the Singapore Strait. Territories to the north, including the Malay Peninsula and Singapore, fell under the British sphere of influence. Territories to the south, including Sumatra and the Riau–Lingga Archipelago, came under Dutch influence.
That line split the Johor–Riau–Lingga–Pahang Sultanate into two. Before the treaty, it had been a single Malay political entity that united territories on both sides of the strait.
The two colonial powers then installed two sultans from the same royal family to rule the separate territories. With British support, Tengku Hussein was crowned Sultan of Johor. He ruled Singapore and mainland Johor.
Meanwhile, Tengku Abdul Rahman was crowned Sultan of Riau–Lingga, with his royal capital in Daik, Lingga.
The entire process, including the signing of the treaty in London, took place without the involvement of the sultan or the nobility of Johor, Pahang, Riau, and Lingga.
The Line That Became a Border
The territorial arrangement established by the treaty soon produced administrative consequences. In 1826, the East India Company merged Penang, Malacca, and Singapore into a single colonial administration known as the Straits Settlements.
This became the foundation of British administration on the Malay Peninsula. It later evolved into present-day Malaysia and Singapore, separate from the Dutch East Indies, which eventually became Indonesia.
A study on international law published in the Journal of East Asia and International Law in 2020 questioned the treaty's legal validity. According to the study, Britain and the Netherlands were only authorized to define their respective spheres of colonial influence.
They did not have the legal authority to transfer sovereignty over territories that did not legally belong to them.
Regardless of this legal debate, the line drawn in London in 1824 remains the direct basis for the Indonesia–Malaysia border that exists today.
