What countries are monotheistic?

Answer 1

Regions or religions?

If you mean the latter, the most famous are the Abrahamic religions, ie; those in which the Biblical figure Abraham is recognised - Judaism, Christianity and Islam. Sikhism is also monotheistic, in that followers believe in one single world creator who has many names.

Many religions recognise lesser deities who are subservient to a greater god - examples whuld include some forms of the Chinese Shangdi, Mohism and Tian which believe in the existence of Heaven as an omnipotent force. Mohim is perhaps the most monotheistic of the traditional Chinese religions in that it teaches that the lesser gods exist merely to carry out Heaven's will. Some forms of Hinduism are also monotheistic, for example Vaishnavism which teaches the supremacy of Vishnu or the Saivites who believe that Siva is the supreme god.

Baha'i teaches that while there are countless interpretations of gods and their natures, all are manifestations of the Oneness of God. As this oneness forms one of Baha'i's core beliefs, the religion can be considered strongly monotheistic despite recognising all gods.

(If you meant to write regions, the answer is all those in which followers of monotheistic religions live. Examples would be the United Kingdom, the USA and India; as all of these are home to Christians, Jews, Muslims and other followers of monotheistic religions - however, since they are also home to those who follow non-monotheistic religions such as branches of Hinduism other than those that are monotheistic such as those listed above, they are also non-monotheistic regions.)