Ptolemy I definition of Ptolemy I in the Free Online Encyclopedia.

Ptolemy I (Ptolemy Soter) (tŏl`əmē sō`tər), d. 284 B.C., king of ancient Egypt, the first ruler of the Macedonian dynasty (or Lagid dynasty), son of a Macedonian named Lagus. He was one of the leading generals of Alexander the Great, and after Alexander's death (323 B.C.) he joined the other Diadochi Diadochi (dīăd`əkī) [Gr.,=successors], the Macedonian generals and administrators who succeeded Alexander the Great .
..... Click the link for more information. in dividing and quarreling over the empire. Ptolemy received Egypt and managed to keep control of it in the midst of incessant warfare. To strengthen his position he married Eurydice, daughter of Antipater Antipater (ăntĭp`ətər), d. 319 B.C., Macedonian general.
..... Click the link for more information. (though he soon shifted his affection to her niece and his own half sister, Berenice Berenice (bĕrənī`sē), b. c.340 B.C., d. 281 or 271 B.C., consort and half sister of Ptolemy I, king of ancient Egypt.
..... Click the link for more information. ). He defeated (321) Perdiccas Perdiccas (pərdĭk`əs), d. 321 B.C., Macedonian general under Alexander the Great.
..... Click the link for more information. , and he at first supported Antigonus I Antigonus I (Antigonus the One-Eyed or Antigonus Cyclops) (ăntig`ənəs sī`klo˘ps), 382?–301 B.C.
..... Click the link for more information. in the confused struggle for imperial power. He defeated Eumenes Eumenes (y

`mĭnēz), c.361–316 B.C.
..... Click the link for more information. , then fearing Antigonus' efforts to remake the empire, allied himself with Cassander Cassander (kəsăn`dər), 358–297 B.C., king of Macedon, one of the chief figures in the wars of the Diadochi .
..... Click the link for more information. and Lysimachus Lysimachus (līsĭm`əkəs), c.355–281 B.C., Thessalian general of Alexander the Great.
..... Click the link for more information. . Ptolemy defeated the troops of Antigonus in 312 but he was defeated at Salamis in 306, and the ultimate defeat and death of Antigonus at Ipsus in 301 resolved the situation. Ptolemy had already declared himself king in 305. Subsequently he laid the outline for Ptolemaic administration in Egypt and did much to make Alexandria a fountainhead of culture and art by founding the library there. Through Arrian, we know that he wrote a history of Alexander.

Bibliography

See J. P. Mahaffy, The Empire of the Ptolemies (1895); E. R. Bevan, A History of Egypt under the Ptolemaic Dynasty (1927); P. M. Fraser, Ptomemaic Alexandria (3 vol., 1972, repr. 1984).