The Ptolemaic dynasty, sometimes also known as the Lagids or Lagidae, was a Macedonian Greek royal family, which ruled the Ptolemaic Kingdom in Egypt during the Hellenistic period. Their rule lasted for 275 years, from 305 to 30 BC. They were the last dynasty of ancient Egypt.
Ptolemy, one of the seven somatophylakes of Macedon who served as Alexander the Great's generals and deputies, was appointed satrap of Egypt after Alexander's death in 323 BC. In 305 BC, he declared himself Ptolemy I, later known as Sōter "Saviour". The Egyptians soon accepted the Ptolemies as the successors to the pharaohs of independent Egypt. Ptolemy's family ruled Egypt until the Roman conquest of 30 BC.
Like the earlier dynasties of ancient Egypt, the Ptolemaic dynasty practiced inbreeding including sibling marriage, but this did not start in earnest until nearly a century into the dynasty's history. All the male rulers of the dynasty took the name Ptolemy, while queens regnant were all called Cleopatra, Arsinoe or Berenice.