In 1025 CE, the South Indian Chola Empire invaded its near-peer power, the Malay Srivijayan Empire. Both entities, previously friendly trading partners, were now in a state of war, which the Cholas almost won after sacking Palembang. In desperation, the Srivijayan emperor (who escaped to Java) sought aid from any direction. The existence of Oceanyka, then perceived by the Malay world as a dangerous land populated by warlike peoples, was well known. It was here that the emperor sought men to fight in his counterattack against Chola forces, which were now planning to cross into Java. Over 5,000 northern colonists, hailing from a variety of cultures and ethnicities, enlisted to fight for the Srivijaya as the "Mercenary Army". For three years they remained in the service of the Malays, fighting on land and sea with enormous courage. Many learned Old Malay, made friends and even married with inhabitants of the Nusantara. A number of Javanese became part of the Mercenary Army as camp followers, by enlisting or as hired specialists (primarily engineers and navigators). Many of these would later migrate to northern Oceanyka.
By 1028, Chola forces had found themselves exhausted and unable to continue their campaigns against Srivijaya. Though Sumatra had been lost, total collapse was avoided by consolidating power in the much richer island of Java, unifying it under a single throne. Expansion to the east made trade and relations with northern Oceanykan polities, many now allied to the Srivijaya, far easier. Much of the Mercenary Army returned home loaded with trinkets and precious metals, though some stayed behind and made up the core of the Srivijaya's palace guard. Contact between Oceanykans and Malays intensified enormously following this historical episode, leading to the Early Middle Ages and a recovery of Oceanyka's own civilisation.