[steve19]

That would not have been about the Sahara, but about Arabia.

If you look at some Sat photos of Saudi Arabia you will see some crazy large circular meadows. They have greened the desert. Almarai is one of the world's largest dairy farms.

[crooked-v]

More broadly, the Middle East in general was once extraordinarily bountiful, but the cumulative effects of natural climate change and thousands and thousands of years of saltwater irrigation have unfortunately desertified much of the region.

[parasense]

Well yeah, and also considering that natural climate change was the most significant issue. Since the Pleistocene ice age ended around 11 thousand years ago, and ever since then the equatorial regions have changed dramatically. Coincidentally this is about the beginning of recorded history, or at least the parts recovered from antiquity. The regions around north Africa, the Arabian peninsula, etc... they all would have been ideal habitats for hominids given the climate of the Earth back then, most of the habitable zones were near the equator during the last ice age, and began expanding north/south as the Ice melted. Likewise the grasslands of north Africa, and Arabian peninsula began to slowly change into arid deserts while the other places thawed.

It's a pity the cradle of civilization turned to sand, but at the cost of Earth becoming more habitable it's a fair trade.

[singularity2001]

Would the Sahara have turned into a desert without millennia of overgrazing and over-burning?

[cmarschner]

One of the cradles, the other being the Chinese, which was lucky enough to be in a lusher climate.

[cheez]

Sure but the idea still stands.