Ahmad Shah I of Pahang

Sultan Ahmad Shah I ibni Almarhum Sultan Mansur Shah (died 1512) is the second Sultan of Pahang who reigned from 1475 to 1495. He succeeded on the death of his younger brother who was poisoned in 1475.
Early life.
Known as Raja Ahmad before his accession, he is the first son of the sixth Sultan of Melaka, Mansur Shah by his wife Putri Wanang Sri Lela Wangsa, daughter of Maharaja Dewa Sura, ruler of Pahang and a relative of the King of Ligor. Both his mother and grandfather were captured and presented to the Sultan of Melaka after the conquest of Pahang.
Raja Ahmad should have been the first Sultan of Pahang, instead, his younger brother Raja Muhammad came before him after being banished from Melaka for committing murder in 1470. He was also passed over from accession to the Melaka throne, in favour of a younger half-brother who became Alauddin Riayat Shah of Melaka. This event led to his resentment towards his half-brother in many years to come. Raja Ahmad went into exile in Pahang, later appointed as Sultan in the place of his brother who died in 1475.
Reign.
Relations between Melaka and its vassal state, Pahang deteriorated greatly after Raja Ahmad's accession. In 1488, Alauddin Riayat Shah died at Pagoh on the Muar river. Rumours spread that the Sultan was poisoned by the order of rulers of Pahang and Indragiri. And when Mahmud Shah succeeded his father on the Melaka throne, the enmity between the uncle in Pahang and the nephew in Melaka continued.
Ahmad Shah bore the slights and insults from Melaka with rancour. He particularly took umbrage of Mahmud Shah's abduction of the Pahang Bendahara's daughter, Tun Teja, who was betrothed to him.
Abdication.
Helpless to avenge and shamed beyond endurance before his subjects, Ahmad Shah abdicated in favour of his very young son, Raja Mansur. The new ruler was placed under the guardianship of his cousins, the three sons of Muhammad Shah. In describing Ahmad Shah's life after the abdication, the "Malay Annals" noted: "his highness went upstream for so long as the royal drums could be heard; when he came to Lubuk Pelang (in present day Jerantut constituency) there he resided, and the sound of the drums was no longer heard. He went into religious seclusion; he it is whom people call "Marhum Syeikh"."