Bahrain

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b. The regime of the Kingdom of Bahrain is that of a hereditary constitutional monarchy, which has been handed down by the late Sheikh Isa bin Salman Al Khalifa to his eldest son Sheikh Hamad bin Isa Al Khalifa, the King. Thenceforward it will pass to his eldest son, one generation after another, unless the King in his lifetime appoints a son other than his eldest son as successor, in accordance with the provisions of the Decree on inheritance stated in the following clause.
c. All provisions governing inheritance are regulated by a special Royal Decree that will have a constitutional character, and which can only be amended under the provisions of Article 120 of the Constitution.
… (Art. 1)

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b. Legislative authority is vested in the King and the National Assembly in accordance with the Constitution. Executive authority is vested in the King together with the Council of Ministers and Ministers, and judicial rulings are issued in his name, the whole being in accordance with the provisions of the Constitution. (Art. 32)

a. The King is Head of State, and its nominal representative, and his person is inviolate. He is the loyal protector of the religion and the homeland, and the symbol of national unity.
b. The King safeguards the legitimacy of the government and the supremacy of the Constitution and the law, and cares for the rights and freedoms of individuals and organizations.
… (Art. 33)