Simon bar Kokhba was a Jewish military leader who led a revolt against the Romans in AD 132. He subsequently established an independent state of Israel which he ruled for three years as Nasi (Prince or President). His state was conquered by the Romans in AD 135 following a two-year war. Originally named Simon Bar Koziba, he was given the name Bar Kochba ("Son of a Star" in Aramaic) by the Jewish sage Rabbi Akiva (or Akiba), who contemplated the possibility that Bar Kochba would be the long-awaited Jewish Messiah.

Due to the failure of an earlier Jewish revolt in the eastern Roman provinces, Bar Kochba's support was mostly limited to the Roman province of Judea. Despite some initial successes, his revolt was brutally crushed by Hadrian: Bar Kochba and his followers were killed in a dramatic last stand at the fortress of Betar, southwest of Jerusalem, and many of his supporters were executed, among them Rabbi Akiva. Nevertheless, it was a costly victory for Rome, and the generals, when reporting to the Senate, did not begin with the customary greeting: "I and my troops are well." After Bar Kokhba's defeat, Jerusalem was razed, Jews were forbidden to live there, and a new Roman city, Aelia Capitolina, was built in its place.

Over the past few decades, much new information about the Bar Kokhba's revolt has come to light, thanks mainly to the discovery of several collections of letters, some possibly by Bar Kokhba himself, in the caves overlooking the Dead Sea. These letters can now be seen at the Israel Museum.