Pekanbaru is the capital of Indonesian province of Riau, and a major economic center on the eastern part of Sumatra Island. Its name is derived from the Malay words for ‘new market’ (‘pekan’ is market and ‘baru’ is new). It has an area of 632.26 km² with a population of 1,093,416.Located on the banks of the Siak River, which flows into the Strait of Malacca, Pekanbaru has direct access to the busy strait and long known as a trading port. Pekanbaru was originally built as a market by Minangkabau merchants during the 18th century.
A settlement has existed on the site since the 17th century. In the late 19th century, the city was developed to serve the coffee and coal industries, and the Dutch built roads to help ship goods to Singapore and Malacca. This city has an airport called Sultan Syarif Kasim II International Airport, and a port called Sungai Duku that is located by the Siak River.
The origin of Pekanbaru was inseparable from the existence of the Siak River as a distributing route for commodities from the Minangkabau Highlands to the Strait of Malacca. During the 18th century, Senapelan region on the banks of the Siak River became a market for the Minangkabau merchants. Over time, the area evolved into a crowded residential area. On June 23, 1784, based on the consultative meeting of the Council of Ministers from Sultanate of Siak Sri Indrapura, consisting of four leaders (datuk) of Minangkabau tribes (Pesisir, Limapuluh, Tanah Datar and Kampar), the area was named Pekanbaru. This date was later celebrated as the anniversary of this city.
The history of Riau before Indonesian independence time has been rooted in the history of Siak Sri Indrapura, a Malay Islamic kingdom. The Siak-centred sultanate was founded by Sultan Abdul Jalil Rahmad Shah in 1725. The first Sultan died in 1746 and later posthumously given the title of Marhum Buantan. The reign was continued to Sultan Abdul Jalil Muzaffar Shah (1746–1765) who ruled for about 19 years. This second Sultan succeeded in making the Kingdom of Siak Sri Indrapura strong and triumphant.
The inauguration of Hashim Abdul Jalil Muzaffar Shah as Sultan of Siak in 1889 in the presence of Resident of North Sumatra W.J.M. Michielsen, chief police Van der Pol and assistant resident Schouten.
The third Sultan was Abdul Jalil Jalaluddin Shah (1765–1766) had only ruled for a year. His real name was Tengku Ismail. His reign was under attacks of the Dutch East India Company (VOC) which took advantage of Tengku Alam (later became the fourth Sultan) as a shield. Sultan Abdul Jalil later dubbed Marhum Mangkat di Balai. Tengku Alam (1766–1780) ascended to the throne after the death of Abdul Jalil Jalaluddin, with the title of Sultan Abdul Jalil Alamuddin Syah and posthumously given the title of Marhum Bukit.
The daughter of fourth Sultan, Abdul Jalil Alamuddin Syah, Badriyyah was married to a person knowledgeable in Islam Sayyid Uthman bin Abdurrahman bin Sa’id bin Ali bin Muhammad bin Hasan bin Umar Banahsan, a Hadhrami of Ba ‘Alawi sada family. Uthman was then appointed as a military commander and religious advisor in the Sultanate. Six of their descendants from this marriage became Sultans, 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 1889–1908. During his rule, many buildings were constructed which now have become the evidence of the Kingdom of Siak. He died in 1908 and was posthumously granted the title Marhum Baginda.
Post Anglo-Dutch Treaties of 1870–71, the colonial government created the Siak Residency in 1873, which covers the entire northeast coast of Sumatra to the sultanate of Deli. The transfer of the capital of the Oostkust van Sumatra residentie (Residency of East Coast Sumatra) in 1887 from Siak to Medan, the capital of Deli, confirms the loss of importance of the sultanate to the Dutch.
The last Sultan of Siak was Syarif Qasim Abdul Jalil Syaifuddin (Syarif Qasim II, who was in throne in 1915–1949). The sultan with real name Tengku Sulong went to the throne seven years after the death of his father Sultan Hashim. In November 1945, Sultan Syarif Qasim II sent a cable to President of the Republic of Indonesia declaring allegiance to the newly created Government of the Republic of Indonesia. Not only that, the Sultan also handed over his property for the struggle of independence of the Republic of Indonesia.