The catapult (katapeltikon) was developed around 400 BC by engineers and craftsmen assembled by Dionysius I of Syracuse. Catapults are mentioned in Athens in the 360s and 350s BC, and by the 330s young men were routinely trained in their use. During these years, artillery appears to have been considered as a defensive weapon. They finally appear in the hands of an aggressor in 340 BC when Philip of Macedon assaulted Perinthus, but it was left to Alexander to fully develop the use of catapults. Under the Romans, catapults initially went through some minor variations with a view to improving their performance. This title decribes the development and operational use of siege artillery throughout the classical period.