Sultan Alauddin Ri'ayat Syah al-Kahar (died 29 September 1571) was the third sultan of Aceh, and was one of the strongest warrior rulers in the history of the sultanate. In his time the power structures that his father had begun were greatly strengthened. His age was marked by warfare with his Portuguese and Malay rivals, with varying degrees of success. Taking power Alauddin was the son of Sultan Ali Mughayat Syah who founded the state in the early 16th century. After Sultan Ali's death in 1530, his eldest son Salahuddin ruled for a while but was inept in governing the sultanate. The queen mother had great influence in the state and appointed a regent called Raja Bungsu who had a green payung (parasol), a symbol of authority, and a house opposite the royal abode. Meanwhile, Alauddin governed Samudra Pasai which had been conquered by Aceh in 1524. Being dissatisfied with conditions in the capital, he staged a royal coup in c. 1537 or 1539, killed Raja Bungsu, and imprisoned Salahuddin and the Queen Mother Sitt Hur, who would die years later in 1548 and 1554 respectively. Alauddin now took the throne with the regnal title Sultan Alauddin Ri'ayat Syah al-Kahar. Under Acehnese tradition he is remembered as a great organizer of the Acehnese state. Thus he was supposedly the ruler who divided Acehnese society into administrative lineage groups (kaum or sukeë), but it is unclear whether this attribution is correct. Conquests on Sumatra The campaigns of Alauddin began in 1539 when he waged war on the Batak people, who lived to the south of Aceh. The Portuguese traveler Fernão Mendes Pinto mentions that the sultan asked the king of the Bataks to convert to Islam, and attacked him when he refused. Pinto provides a long and picturesque account of the Bataks and their affairs with the Acehnese; it is doubtful from the point of view that no comprehensive Batak kingdom is known to other sources. The Acehnese army reportedly included contingents of Turks and men from Cambay and Malabar. After this campaign Alauddin attacked the Aru Kingdom, (the later Deli Sultanate). He killed the ruler of Aru in 1539, but was then forced by the Johor Sultanate's army to withdraw in around 1540, Aru subsequently belonged to Johor up to 1564. Enterprises against Melaka and Johor The principal enemy was, however, Melaka, which was held by the Portuguese since 1511.