Which prehistoric period made parts of the Sahara wetter and more densely inhabited?

The African Humid Period made parts of the Sahara wetter and more densely inhabited.

This interval occurred broadly during the early and middle Holocene, roughly from 14,500 to 5,000 years ago, although its timing varied across Africa. Stronger summer monsoon rainfall transformed many areas now covered by desert into grasslands, wetlands and lake landscapes.

Archaeological evidence shows that people lived across regions that are now extremely arid. Rock paintings and engravings depict cattle, wild animals and scenes associated with wetter environments. Ancient lake sediments and pollen records also document the former presence of vegetation and standing water.

The humid phase ended as Earth’s orbital configuration gradually reduced Northern Hemisphere summer sunlight, weakening the African monsoon. The Sahara became progressively drier, though the transition was not identical everywhere or at exactly the same time. The period is sometimes called the Green Sahara, but that phrase describes a broad environmental phase rather than a permanently forested landscape.