I always thought “atlases” — books of maps, that is — were named after Atlas, the Greek titan who carries the earth on his shoulders (see above). And it is indeed he who appears on an engraving of Tavole Moderne Di Geografia De La Maggior Parte Del Mondo Di Diversi Autori , a collection of maps published by Antonio Lafreri in 1572. However, it was Gerardus Mercator, the legendary map-maker, who invented the term and apparently he did not have the Greek titan in mind at all but rather “Atlas of Mauretania,” a famous philosopher, mathematician, and astronomer, who also was king of Mauretania. Not very much is known about this man, however. Wikipedia has next to nothing.
“Mauri,” from which “Mauretania” is derived, was the Roman term for the Berber kingdoms of North Africa. But this is also where the Atlas mountains are located. In fact ádrār in Berber means “mountain.” The Atlantic Ocean was named after Atlas and so was the lost island of Atlantis. Moroccans seem to have been great geographers. Ibn-Batuta was from Morocco too.