Qanun is an Arabic word (Arabic: قانون, Qānūn; Ottoman Turkish: قانون, Ḳānūn) derived from the Greek κανών (kanōn, the root for the modern English word "canon"). It can refer to laws established by Muslim sovereigns, in particular the Ottoman Sultans, in contrast to shari'a, the body of law elaborated by Muslim jurists. It is thus frequently translated as "dynastic law". The idea of kanun first entered the Muslim World in the thirteenth century, as it was borrowed from the Mongols in the aftermath of their invasions. The 10th sultan of the Ottoman Empire, Suleiman was known in the Ottoman Empire as Suleiman Kanuni ("the Lawgiver"), due to his code of laws.
After the fall of the Abbasids in 1258, a practice known to the Turks and Mongols transformed itself into Qanun, which gave power to caliphs, governors, and sultans alike to "make their own regulations for activities not addressed by the sharia." This became increasingly important as the Middle East started to modernize, thus running into the problems of a modern state, which were not covered by Shariah. The Qanun began to unfold as early as Umar I (586–644 CE). Many of the regulations covered by Qanun were based on financial matters or tax systems adapted through the law and regulations of those territories Islam conquered. Qanun in Arabic means law or rules.