In the legion vs phalanx battle, how come Romans won against long pikes used by phalanx?
The reason why the Roman legions were able to defeat the phalanx formations lies mainly in two separate reasons; maneuverability and professionalism.
The Roman legion was organized into maniples, small groups of around thirty soldiers who were able to create complex formations and move much more quickly than the less organized and larger phalanx force. With these smaller groups the
Romans were able to create holes in the phalanx formations along with being able to flank and surround individual units. This formation system along with the fact that most Roman soldiers were professionally paid and well disciplined soldiers meant that the once formidable phalanx was no match for the more organized Roman force.