Sumer, though technically an empire, was very successful, and they also invented a lot of different things, such as writing(5000-1750 BC). (1 agos 5000 año aC – 2 agos 1750 año aC)
Añadido al timeline:
fecha:
1 agos 5000 año aC
2 agos 1750 año aC
~ 3252 years