The large empire Alexander had conquered was too big for one successor. One general was entrusted with Macedonia another Thrace and a third Syria. One of Alexander's favorite generals Ptolemy was made governor of Egypt. The esteem was mutual as can be seen in Ptolemy's having Alexander's body brought for burial to Egypt where it was permanently interred at the city Alexander had founded and named after himself.

Alexandria was the city Ptolemy made his capital. There he founded a museum and started collecting books for a library.

For more than 350 years the Ptolemies ruled Egypt. Following the general was his son Ptolemy Philadelpus who made the library the best in the world. The books made of papyrus were in Greek or Latin. Ptolemy Philadelphus had the Jewish Bible translated into Greek for his library. He is also known for re-opening a canal between the Red Sea and the Nile providing access between the Atlantic and the Indian Ocean which was important for the wheat trade and enabled Alexandria to become the richest city in the world.

Under the Ptolemies learning was encouraged. Its students first taught that the earth is round and another determined almost the exact diameter of the earth.

The most famous Ptolemy was Cleopatra.