On the eastern side of the Dead Sea and 53 kilometres southwest of Amman is the hilltop fortress of Machaerus. This is the place where John the Baptist - was imprisoned and beheaded.
When Herod the Great died in 4 BC, Machaerus passed to his son Herod Antipas, who ruled Galilee and Perea (an area on the eastern side of the Jordan River) until AD 39.
John the Baptist criticised Herod Antipas, the governor of Galilee and Perea, for unlawfully marrying his half-brother's wife, Herodias — thereby earning her enmity. According to the historian Josephus, John's execution took place at Machaerus.
Herod Antipas had married Phasaelis, daughter of King Aretas of Nabatea, the kingdom whose capital was Petra. While visiting Rome in AD 26 he stayed with his half-brother Herod Philip I and fell in love with Philip's wife Herodias.
When Phasaelis learnt that Antipas intended to divorce her and marry Herodias, she obtained permission to visit Machaerus and from there fled to her father in Nabatea. Antipas's rejection of Phasaelis added a personal note to existing disputes with King Aretas over the boundary of Perea and Nabatea. In AD 36 Aretas attacked Antipas and completely destroyed his army.
Some time before the war with Aretas, Jesus was arrested in Jerusalem and brought before Pontius Pilate. When Pilate learnt that Jesus came from Galilee, he sent him to Herod Antipas, who was also in Jerusalem at the time.
Herod Antipas was accused of conspiring against the Roman emperor Caligula, who exiled him to Gaul in AD 39.