which was started since the seventh Sultan of Siak Sri Indrapura (hence their names prefixed with word Syarif or Sayyid). The book of pedigree Shamsu al-Dzahirah, which is the book of the Ba 'Alawi sada genealogy authored by Sayyid Abdurahman bin Mohammed Al-Mashoor (mufti of Tarim), and several other books such as Shajarah al-Zakiyah written by Yusuf bin Abdullah Jamalullail and al-Mu'jam al-Latif li Asbab al-Alqab wa al-Kunya fi al-Nasab al-Sharif by Sayyid Muhammad bin Ahmad al-Shatri, discuss the family history of Siak Sultanate which many people mistakenly think as of the Shahab families. This has also been verified by the institution for that purpose, al-Rabithah al-Alawiyah. The last name Shahabuddin given to Usman bin Abdurrahman who was married to the daughter of the Sultan of Siak is actually just a title, as well as titles given to his grandchildren such as Syaifuddin, Khaliluddin, or Jalaluddin. Nevertheless, many descendants of Sayyid Usman bin Abdurrahman in Malaysia still use the Shahab title. The fifth in throne was Sultan Muhammad Ali Abdul Jalil Muazzam Shah (1780–1782). During his reign the Sultanate of Siak relocated to Senapelan (now Pekanbaru). He is also the founder of the city of Pekanbaru, so since his death in 1782 he was titled with title Marhum Pekan. Sultan Yahya Abdul Jalil Muzaffar Shah later took the position as the sixth sultan during 1782–1784. Like the previous sultan, Sultan Yahya also only had 2 years to rule. He died in 1784 and was posthumously granted the title Marhum Mangkat di Dungun. The seventh Sultan, Ali Abdul Jalil Syaifuddin Ba'alawi, was the first sultan of Arab descent and holds the title al-Sayyid Sharif. During his reign the Kingdom of Siak reached its peak. He died in 1810 and was posthumously granted the title Marhum Kota Tinggi. Ibrahim Abdul Jalil Khaliluddin was the eight sultan in the kingdom in 1810–1815, where his real name was Ibrahim. He died in 1815 and then was named the Marhum Mempura Kecil. He was then followed by Sultan Syarif Ismail Abdul Jalil Jalaluddin Ismail who took the reign during 1815–1854 which was given title Marhum Indrapura. He was then followed by the next sultan, Qasim Abdul Jalil Syaifuddin I (Sharif Qasim I, ruled in 1864 to 1889). He died in 1889 and was posthumously granted the title Marhum Mahkota. His son, Syarif Hashim Abdul Jalil Muzaffar Shah was then raised to the throne during period