The length of the period of breastfeeding depends on many factors, both individual and cultural or environmental ones. In human societies that have no access to easily digested food alternatives (this refers to foragers in particular) this period is usually longer, while in farming communities, where infants are fed with porridge or yoghurt, it can be shortened. This implies demographic consequences: a mother who breastfeeds her child for a shorter time can have more children, therefore, the breastfeeding period influences the birth rate.
Sumerians are known as the founders of the urban civilization that dominated in southern Mesopotamia in the 4th and 3rd millennia BC. They developed a network of irrigation channels that made it possible to cultivate cereals in desert areas of the Lower Euphrates, introduced an ideographic script, initially pictographic and then simplified to the form of cuneiform characters impressed in wet clay, built the biggest cities in the world at that time, with monumental temples and enormous palaces.
Kings of Mari controlled an important trade route in the valley of the Euphrates River in the 3rd and early 2nd millennium BCE. Although their country was situated in an area with unfavourable conditions for agriculture, the economy of the kingdom of Mari could support a big population. The key to understanding this paradox is animal dung.
The kingdom of Mari was the most powerful country of north Mesopotamia in the 3rd and early 2nd millennium BC. Its power is reflected both by the size of its capital (modern archaeological site of Tell Hariri), which occupied an area of more than 60 hectares – more than Cracow in the 13th century – and by the fact that six of its rulers were included in the Sumerian King List, that is a record of the dynasties that were regarded as those holding superior power in Sumer. The dynasty from Mari was the only dynasty from north Mesopotamia on this list.