European Colonialism was responsible for a whole era of barbaric killing, plundering, indigenous genocides, and industrialized slave trade industry. Sure, that happened by many throughout history, by various groups, but that doesn't mean Europe won't get it's own special recognition for being born on the ashes and fortunes of those slain by a collection of evil empires. Most slavery people are aware of today are an extension of the European Colonial slave trade and the European trade industry it catered to.