The military campaigns of the Aceh Sultanate challenge both the naval dominance of the Portuguese and the holdings of the Sultanate of Johor on Sumatra.

The victories of the 1520s expand Aceh’s territory, creating a powerful kingdom that will endure until the Aceh War (1873–1903). However, its struggle with the Portuguese remains relentless.

In 1527, Portuguese captain Francisco de Mello sinks an Acehnese vessel at the roadstead outside the capital, killing the crew. The following year, Simão de Sousa Galvão, forced by a storm to seek shelter in Aceh, is attacked by local forces—most of the foreigners are killed, and the survivors taken prisoner.

Sultan Ali Mughayat Syah begins peace negotiations, which halt a planned joint expedition by Aru and the Portuguese. However, new hostilities soon follow, and the sultan orders all Portuguese prisoners executed.

In 1529, Sultan Ali devises a surprise attack on Melaka, but news of the plan leaks, and the invasion never materializes.

The date of Sultan Ali Mughayat Syah’s death is uncertain, with later chronicles offering conflicting accounts—1511, 1522, or 1530. However, his gravestone records his passing as August 7, 1530, exactly one month before the death of his abdicated father, Syamsu. Both are buried in the palace compound of Kutaraja (now Banda Aceh).

Portuguese chronicler João de Barros alleges that Sultan Ali was poisoned by his wife, Sitt Hur, a sister of the ruler of Daya, in revenge for Aceh’s conquest of her homeland. She outlives him by twenty-four years, passing away on December 6, 1554.

Sultan Ali leaves behind two sons, Salahuddin and Alauddin al-Kahar. Salahuddin, who lacks his father’s military acumen, succeeds him on the throne, while his younger brother, Alauddin, will lay the true foundations of Aceh’s power after 1539.