Why not
In about 3000 BCE, their first city, Ur, was established. By about 2500 BCE they had established a ruling system that involved dynasties.
The Sumerian's City-States depended on the swamp lands located between the Tigris and Euphrates rivers' Fertile Crescent. Due to the constant flooding, this Fertile Crescent formed by making the Persian Gulf to recede from its previous shores. The floods brought much fertile top soil down from the mountains that gradually filled that section of the Persian Gulf. The Sumerians had built high walls around their city to divert the periods of flooding waters. This swamp land being plowed and used for Sumer's agricultural land, that fed their people, had gradually brought up a salty water that would kill their crops. The land became not fit to grow anything. So the Sumerians had to relocate to a better land for to grow their crops as to feed their people.
Mesopotamia is the land between the Tigris and Euphrates Rivers. Sumerians learned to control the Tigris and Euphrates Rivers by constructing levees and irrigation canals.
It put them closer to the stars, from which they believed we came.
Why not
Sumer is the land in lower Mesopotamia where the Sumerians settled.
the land was fertile
fertile farming land
why did the sumerians decide to live in fertile crescent
They wanted fertile land.
sumerians were the people in fertile crescent sumerians were the people in fertile crescent
That was where the fertile land was, on which they depended.
Sumerians
because the land was fertile enough to grow food
The land near rivers has fertile soil.
3500 BC.about