There are various versions of the storytelling associated with the origins of Mengkabong according to the older generations who settled in Mengkabongfor generations. In 1741, Mengkabong became the earliest major naval base during the reign of Sultan Omar Ali Saifuddin I. Among the individuals who was responsible for maintaining peace in the Mengkabong area is the Raja Tua. Raja Tua was appointed as the commander-in-chief of the navy in Mengkabong. SOAS I has ordered the Raja Tua to build a naval base and attack, eradicate the issue of slave hunters and maintain peace in Mengkabong. This study focuses on the origins and role of the Raja Tua as the commander-in-chief of the navy in Mengkabong. Raja Tua helped the people in Mengkabong during the reign of SOAS I. He managed to gather and unite Bajau and Dusun ethnics and maintained peace in Mengkabong. Raja Tua also trained four of his children named Embo Ilang, Embo Pat, Embo Kudrat and Embo Anting to help him governing Mengkabong. This study uses primary sources, secondary sources, interviews, genealogies and personal collections to discuss the origins and role of the Raja Tua in Mengkabong. In addition, this study also involved fieldwork at Mengkabong to see the abandoned tombs and former forts to strengthen the evidence and facts on Mengkabong