The next event we hear of in the history of the city is its conquest by Alexander the Great (331 B.C.), and later by Ptolemy Lagi and Demetrius Poliorcetes.
In 294 B.C. he was defeated at Mantineia by Demetrius Poliorcetes, who invaded Laconia, gained a second victory close to Sparta, and was on the point of taking the city itself when he was called t So Plut.
Three years later Demetrius set off to reconquer the eastern provinces from the Parthians, leaving Queen Cleopatra tr) maintain his cause in Syria.
But in 147 Philometor broke with him and transferred his support, together with the person of Cleopatra, to Demetrius II., the young son of Demetrius I.
The practice by which the king associated a son with himself, as secondary king, dates from the very beginning of the kingdoms of the Successors; Antigonus on assuming the diadem in 306 caused Demetrius also to bear the title of king.
Hated for his vices, Demetrius fell in battle against the usurper, Alexander Balas, in 150 B.C.
The sudden death of the tsarevich Demetrius at Uglich (May 15, 1591) has commonly been attributed to Boris, because it cleared his way to the throne; but this is no clear proof that he was personally concerned in that tragedy.
The kings after Alexander, with the exception of Demetrius Poliorcetes and Pyrrhus, are not found to have more than one legitimate wife at a time, although they show unstinted freedom in divorce and the number of their mistresses.
Philadelphus, but Arsinoe, disliking the projected alliance, induced Demetrius the Fair, son of Demetrius Poliorcetes, to accept the throne of Cyrene as husband of Berenice.
In 153 Alexander Balas withdrew Jonathan from his allegiance to Demetrius by the offer of the high-priesthood.