The Middle East is a geopolitical region spanning most of West Asia, along with Egypt in Africa and Turkey in Europe, historically known as the "Near East." Today, 13 of its 18 countries are part of the Arab world, with Egypt, Iran, and Turkey being the most populous, Saudi Arabia the largest by area, and Arabs, Turks, Persians, Kurds, Jews, and Assyrians forming its main ethnic groups. As the first region settled by modern humans outside Africa and the birthplace of writing systems and several cradles of civilization, it is also the origin of the three core Abrahamic religions—Judaism, Christianity, and Islam. The region is largely hot and arid, but major rivers like the Nile, Tigris, and Euphrates support agriculture, while the Persian Gulf states hold vast petroleum reserves, making the area highly vulnerable to climate change and water scarcity. The term "Middle East" was popularized by American naval strategist Alfred Thayer Mahan in 1902, who used it to describe the strategically vital area between Arabia and India during the Anglo-Russian "Great Game." This combination of rich history, strategic location, and energy resources continues to make the Middle East a focal point of global politics.