Editing Ptolemy III Euergetes (section)

==Background and early life==
Ptolemy III was born some time around 280 BC, as the eldest son of [[Ptolemy II]] and his first wife [[Arsinoe I]], daughter of King [[Lysimachus]] of [[Thrace]]. His father had become co-regent of Egypt in 284 BC and sole ruler in 282 BC. Around 279 BC, the collapse of Lysimachus' kingdom led to the return to Egypt of Ptolemy II's sister [[Arsinoe II]], who had been married to Lysimachus. A conflict quickly broke out between Arsinoe I and Arsinoe II. Sometime after 275 BC, Arsinoe I was charged with conspiracy and exiled to [[Coptos]].<ref name=H36>{{harvnb|Hölbl|2001|p=36}}</ref> When Ptolemy II married Arsinoe II probably in 273/2 BC, her victory in this conflict was complete. As children of Arsinoe I, Ptolemy III and his two siblings seem to have been removed from the succession after their mother's fall.<ref name=BArsII>{{cite web |last1=Bennett |first1=Chris |title=Arsinoe II|url=http://instonebrewer.com/TyndaleSites/Egypt/ptolemies/arsinoe_ii_fr.htm|website=Egyptian Royal Genealogy |access-date=10 October 2019}}</ref> This political background may explain why Ptolemy III seems to have been raised on [[Thera]] in the Aegean, rather than in Egypt.<ref>''[[Inscriptiones Graecae|IG]]'' XII.3 464</ref><ref name=CBP3>{{cite web |last1=Bennett |first1=Chris |title=Ptolemy III|url=http://instonebrewer.com/TyndaleSites/Egypt/ptolemies/ptolemy_iii_fr.htm|website=Egyptian Royal Genealogy |access-date=13 October 2019}}</ref> His tutors included the poet and polymath [[Apollonius of Rhodes]], later head of the [[Library of Alexandria]].<ref>{{harvnb|Hölbl|2001|p=63}}</ref>

From 267 BC, a figure known as Ptolemy "the Son" was co-regent with Ptolemy II. He led naval forces in the [[Chremonidean War]] (267–261 BC), but revolted in 259 BC at the beginning of the [[Second Syrian War]] and was removed from the co-regency. Some scholars have identified Ptolemy the Son with Ptolemy III. This seems unlikely, since Ptolemy III was probably too young to lead forces in the 260s and does not seem to have suffered any of the negative consequences that would be expected if he had revolted from his father in 259 BC. Chris Bennett has argued that Ptolemy the Son was [[Ptolemy of Telmessus|a son]] of Arsinoe II by Lysimachus.<ref>{{cite web |last1=Bennett |first1=Chris |title=Ptolemy "the son"|url=http://instonebrewer.com/TyndaleSites/Egypt/ptolemies/nios_i_fr.htm|website=Egyptian Royal Genealogy |access-date=10 October 2019}}</ref><ref group=notes>This identification of Ptolemy son of Lysimachus, with Ptolemy the Son who is attested as Ptolemy II's co-regent is argued in detail by Chris Bennett. Other scholars have identified the co-regent as an illegitimate or otherwise unknown son of Ptolemy II.</ref> Around the time of the rebellion, Ptolemy II legitimised the children of Arsinoe I by having them posthumously adopted by Arsinoe II.<ref name=BArsII/>

In the late 250s BC, Ptolemy II arranged the engagement of Ptolemy III to [[Berenice II of Egypt|Berenice]], the sole child of Ptolemy II's half-brother King [[Magas of Cyrene]].<ref>Justin 26.3.2</ref> The decision to single Ptolemy III out for this marriage indicates that, by this time, he was the [[heir presumptive]]. On his father's death, Ptolemy III succeeded him without issue, taking the throne on 28 January 246 BC.<ref name=CBP3/>