Ptolemy I Soter rivals after Alexander's death. For example, Arrian's account of the fall of Thebes in 335 BC ("Anabasis" , a rare section of narrative explicitly attributed to Ptolemy by Arrian) shows several significant variations from the parallel account preserved in Diodorus Siculus (17.11–12), most notably in attributing a distinctly unheroic role in proceedings to Perdiccas. More recently, J. Roisman has argued that the case for Ptolemy's blackening of Perdiccas and others has been much exaggerated. Ptolemy personally sponsored the great mathematician Euclid. He found Euclid's seminal work, the "Elements", too difficult to study, so he asked if there were an easier
Ptolemy II Philadelphus and dissolute, intellectual and artificial, has been compared with the Palace of Versailles of Louis XIV of France. Ptolemy deified his parents and his sister-wife after their deaths. Ptolemy II began his reign as co-regent with his father, Ptolemy Soter, from c. 285 to c. 283 BCE, and maintained a splendid court in Alexandria. Egypt was involved in several wars during his reign. His maternal half-brother Magas had declared himself king of Cyrene in 276 and began a war against Ptolemy's government in 274 BCE. Magas managed to keep Cyrenaica independent of the Ptolemies until his death in 250 BCE.