How many of the ancient river civilizations had slavery

A river gives the inhabitants a reliable source of water for drinking and agriculture. Additional benefits include fishing, fertile soil due to annual flooding, and ease of transportation. The first great civilizations, such as those in Mesopotamia and Egypt, all grew up in river valleys.

the us hoped to prevent any nations from leaning towards soviet union-based communism. the containment policy was established in hopes of keeping communism from spreading to new places.

that’s true, tatiana prouskouriakoff established that the inscriptions were primarily historical.   they recorded events in the lives of mayan rulers and their families.