How long was the rule of the dynasty that was active when the Rosetta Stone was inscribed?
Rosetta Stone The Rosetta Stone is a granodiorite stele, found in 1799, inscribed with three versions of a decree issued at Memphis, Egypt in 196 BC during the Ptolemaic dynasty on behalf of King Ptolemy V. The top and middle texts are in Ancient Egyptian using hieroglyphic script and Demotic script, respectively, while the bottom is in Ancient Greek. As the decree has only minor differences between the three versions, the Rosetta Stone proved to be the key to deciphering Egyptian hieroglyphs.
Chronology of the ancient Near East The chronology of the ancient Near East provides a framework of dates for various events, rulers and dynasties. Individual inscriptions and texts customarily record events in terms of a succession of officials or rulers, taking forms like "in the year X of king Y". Thus by piecing together many records a relative chronology is arrived at, relating dates in cities over a wide area. For the first millennium BC, the relative chronology can be tied to actual calendar years by identifying significant astronomical events. An inscription from the tenth year of Assyrian king Ashur-Dan III refers to an eclipse of the sun, and astronomical calculations among the range of possible dates identify the eclipse as having occurred 15 June 763 BCE. The date can be corroborated with other mentions of astronomical events and a secure absolute chronology established, that ties the relative chronologies into our calendar.