Ptolemy, son of Lagus, was one of the most consequential figures of the early Hellenistic period: eye-witness historian of Alexander's campaigns, satrap and later king of Egypt, founder of Alexandria's most famous institutions and of a dynasty that endured for nearly three centuries. Yet his life does not lend itself to book-length biography because of the patchiness of the sources. So far the endeavour has been attempted only by scholars with a focus on Classical history, resulting in a less than satisfactory treatment of Egyptian topics.

W.M. Ellis's modest Ptolemy of Egypt (1994) is shaped around the historical judgement that Ptolemy's greatest achievements were in the ‘arts of civilization’. In contrast, W. narrates Alexander's campaigns and the Diadochic wars in considerable detail, while acknowledging Ptolemy's limited involvement, and he assesses the veracity of the historical descriptions provided by Ptolemy, in the context of this narrative as well as in an appendix. Both Ellis and W. credit Ptolemy with foresight that Alexander's empire was doomed, but W. rejects the now-frayed consensus that Ptolemy pursued a policy of ‘defensive imperialism’. He presents Ptolemy as patient and cunning, biding his time as he gradually expanded his territories and prestige. The Greek campaign of 309/8 bce is interpreted not as an aberration but as a failed attempt to claim the Macedonian throne.

Other aspects of Ptolemy's career, especially his administration of Egypt, are treated less expansively and less judiciously. In explaining Ptolemy's accommodations to Egyptian culture W. enshrines unsupported assumptions and misunderstandings. Ptolemy is alleged to have prohibited his Egyptian subjects from worshipping him, without evidence or adequate discussion of ruler worship under the pharaohs. Otherwise W. adopts an instrumentalist view of Ptolemy's religious policies. He adheres to the outdated view that Ptolemy founded the cult of Sarapis to unite his ethnically diverse subjects. The Satrap Stela, the most important hieroglyphic monument of Ptolemy's reign, is interpreted solely in terms of military strategy: Ptolemy's gift of land to the priests of Buto was intended to secure their support in the event of an attack, and the possible mention of a Nubian campaign c. 312 bce must be rejected because Ptolemy would not have left Alexandria undefended at a critical juncture. An Egyptian temple relief depicting a ritual offering of maat for Egypt's prosperity is cited as evidence that Ptolemy took seriously his duties as pharaoh, although temple decorations were designed by priests on theological grounds, and there is no reason to assume that this one reflected Ptolemy's royal ideology. A noteworthy anachronism is W.’s repeated invocation of ‘freedom of religion’ as key to Ptolemy's relations with the Egyptians. W. correctly assesses the importance of Ptolemy's economic policies, but here too there are mistakes, such as the claim that Cyrenaica shared a unified monetary system with Ptolemy's other territories. A quick run through the reigns of Ptolemy's successors is marred by further errors of fact and interpretation, including the allegation that the use of Egyptian soldiers in the battle of Raphia increased the social influence of priests and the statement that Ptolemy VIII married his own daughter.