How long was the rule of the dynasty that was active when the Rosetta Stone was inscribed?
Ptolemaic dynasty The Ptolemaic dynasty (Ancient Greek: Πτολεμαῖοι , "Ptolemaioi"), sometimes also known as the Lagids or Lagidae (Ancient Greek: Λαγίδαι , "Lagidai", after Lagus, Ptolemy I's father), 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.
Nanda Empire The Nanda dynasty originated from the region of Magadha in ancient India during the 4th century BCE and lasted between 345–321 BCE. At its greatest extent, the empire ruled by the Nanda Dynasty extended from Bengal in the east, to the Punjab region in the west and as far south as the Vindhya Range. The rulers of this dynasty were famed for the great wealth which they accumulated. The Nanda Empire was later conquered by Chandragupta Maurya, who founded the Maurya Empire.