Sumer (Shumer, Sumeria, Shinar, native ki-en-gir) formed the southern part of Mesopotamia from the time of settlement by the Sumerians (about 4000 BC) until the time of Babylonia (around 2000 BC). Its location was in the southern part of the Tigris-Euphrates plain. It lacked minerals and trees, however, so Sumerian structures where comprised of mud bricks which were not fixed with mortar or with cement. Because bricks (being rounded) are somewhat unstable in behavior, Sumerian bricklayers would lay a row of bricks perpendicular to the rest every few rows. The gaps would be filled with bitumen, grain stalks, marsh reeds, and weeds. Since mud-brick buildings do not last long, were periodically destroyed and levelled, then rebuilt on the same spot. This process of constant rebuilding gradually raised the level of cities and they eventually came to be elevated above the surrounding plain. The left-over hills are known as tells and can befound throughout the ancient Near East.
People from Sumer did not refer to themselves as “Sumerians”. It is a term that was first applied by the Akkadians. The Sumerians called themselves "the black-headed people" (sag-gi-ga) and called their land Ki-en-gi, "place of the civilized lords". Their language was called by them eme.gir.
The Sumerians were unique in their language, culture, and perhaps even appearance. They differed from their Semitic neighbors and are widely believed to have been invaders or migrants to the plains. It is, however, difficult to determine exactly when this event occurred or the original geographic origins of the Sumerians. Nonetheless, some archeologists believe the Sumerians were, in fact, original to the Mesopotamian plains. Others maintain that the name “Sumerian” should only be applied to the language, not the people. These archaeologists believe that there was no separate “Sumerian” ethnic group. Sumerian as a language is isolated in Linguistics because it belongs to no known language family, as for example, Akkadian which belongs to the Hamito-Semitic, or Afro-Asiatic languages.
Source: Wikepedia (http://en.wikipedia.org/wiki/Sumer)
