After Sargon, Sumer was ruled by many different kings and one queen, Queen Kubaba. The city-states were struggling because their lands were not as fertile as they once were.
All river water contains a tiny amount of salt. When the water evaporates, the salt is left behind. Farmers had been using river water to irrigate their crops for thousands of years in Sumer, and the ground was getting saltier. The process of soil collecting salt is called salinization. If the farmers had let their fields rest for a few years, the extra salt would have washed away, but they continued to plant more crops every year. Eventually, the soil became too salty to grow enough food for the people who depended on it.
Sumer also faced attacks from people outside of the city-states. Nomadic barbarians and herders would often raid the cities to get money, goods, and food. The city-states were built on plains along the rivers with no natural defenses. They could not repel the invaders. Many of the invaders were Amorites. These were herding tribes from western Mesopotamia. The Amorites did not conquer Sumer all at once. Instead, one Amorite tribe would take control of a Sumerian city-state. Eventually, most of Sumer was controlled by Amorites.
Sumer was the first known civilization on Earth. It lasted from about 4500 BC to 1900 BC. The people of Sumer built cities and temples. They invented irrigation, writing, the wheel, and sailboats. The most amazing thing about Sumerians is that we didn’t know they existed until the 1800s. We are still learning about the Sumerians and their amazing city-states. Who knows what we will find next?