Sandao (三嶋 in Chinese characters), also known as Sanyu (三嶼) and Sanshu (三洲), were a collection of a prehispanic Philippine polities recorded in Chinese annals as a nation occupying the islands of Jamayan 加麻延 (present-day Calamian), Balaoyou 巴姥酉 (present-day Palawan),[1] and Pulihuan 蒲裏喚 (near present-day Manila).[2] In the Chinese Gazetteer the Zhufan zhi 諸蕃志 (1225), they were described as tributary states of the more powerful nation of Ma-i centered in nearby Mindoro.[3]
They described Sandao as thus:
Sandao remained tributary states of Ma-i until its territories were invaded by Sulu and Brunei marking its end as an independent nation.