The town is named after
Saint Ghislain. In the 7th century, with two unknown disciples Ghislain made a clearing in the vicinity of
Castrilocus (now
Mons), later taking up his abode at a place called
Ursidongus, where he built an
oratory or
chapel dedicated to Saints
Peter and
Paul.
Ursidongus was later named after him. ==Economy==