Bartolom de Las Casas was the first and fiercest critic of Spanish colonialism in the New World. An early traveller to the Americas who sailed on one of Columbus's voyages, Las Casas was so horrified by the wholesale massacre he witnessed that he dedicated his life to protecting the Indian community. He wrote A Short Account of the Destruction of the Indies in 1542, a shocking catalogue of mass slaughter, torture and slavery, which showed that the evangelizing vision of Columbus had descended under later conquistadors into genocide. Dedicated to Philip II to alert the Castilian Crown to these atrocities and demand that the Indians be entitled to the basic rights of humankind, this passionate work of documentary vividness outraged Europe and contributed to the idea of the Spanish 'Black Legend' that would last for centuries.