During this century, three distinct legal systems have been administered within the Gulf region. They are (a) English law or Anglo-Mohammedan law, (b) Shariah or Islamic law, and (c) the National Legal Systems of each individual Gulf State, e.g. Iranian Legal System.

The British predominance in the Gulf was formally established in 1820 under the terms of the “General Treaty with the Arab States for the Cessation of Plunder and Piracy by Land and by Sea”. Bahrain Order in Council 1913 and subsequent Orders enforced British Indian laws in the Gulf Protectorates. This was allegedly necessitated by the lack of “satisfactory legal and judicial systems” in Bahrain and other British Protectorate States. This was not true as far as the Muslims were concerned. The nationals of the Gulf States were satisfied with the operation of the Islamic system assimilating different degrees of local customs. The introduction of English law into the Muslim world, particularly British India and the Gulf area, produced a mixed legal system known as “Anglo-Mohammedan law”. Although the influence of English law is still vividly present in both Indian and Pakistani legal systems, all Gulf States have developed their own codified legal systems since attaining independence.

Bahrain, Qatar, and the seven Trucial States were commonly known as the British Protected States because of their treaty relations with the United Kingdom (1820–1971). However, the Gulf States did not enjoy the status of standard protectorates in which the protecting Power acts merely as agent for the protected Power in conducting international affairs. On the contrary, the U.K. was solely responsible for the international affairs of the Gulf Protectorates in the sense that the Protectorates themselves lacked the legal capacity to conclude directly any international engagements. Furthermore, the internal affairs of these Protectorates were generally, if not strictly, controlled by the U.K. The British Protectorates attained independence in the following order: Kuwait on June 19, 1961, Bahrain on Aug. 15, 1971, Qatar on Sept. 3, 1971, and the UAE on Dec. 1, 1971.

Furthermore, English common law has been adopted as the inspiring source of “modern” or “imported” law in many parts of the Islamic world including Pakistan, Malaya, Northern Nigeria and the Sudan. Only Indonesia has been influenced by the Dutch model, whereas the majority of the Islamic States (e.g. Anglo-phone African States, Arab States and Iran) have been influenced by the French system.