The area on which San Giovanni Rotondo is built, founded in 1095, was inhabited since prehistoric times. Traces of a village dating back to the IV century B.C. can be found in tombs and other remains. The name would appear to derive from a circular (round) baptistery destined in ancient times to the cult of Janus; later the place was consecrated to Saint John the Baptist.
In 1220 it fell under Frederick II who surrounded the town with fortifications and towers. There are numerous churches in the town centre, but now the development of the town is linked exclusively to the figure of Padre Pio.