Answers: Water; Judaism; Christianity; Islam; Shia.
Southwest Asia is a term that defines an area that roughly overlaps with the Middle East, with the exception of North Africa and the inclusion of the Caucasus, although it has no "official" definition.
The area is mostly arid or semi-arid, and this relative lack of water has shaped much of the area's culture and history. However, some major water sources, such as the Tigris and Euphrates rivers, have been home to large population settlements. The area is likely to be one of the birthplaces of agriculture and civilization. It also saw the birth of most major monotheistic religions, such as Judaism, Christianity and Islam.