It was legal in the Byzantine Empire but became rare after the first half of 7th century.[1] From 11th century, semi-feudal relations largely replaced slavery.[2] Under the influence of Christianity, views of slavery shifted: by the 10th century slaves were viewed as potential citizens (the slave as a subject), rather than property or chattel (the slave as an object).[3] Slavery was also seen as "an evil contrary to nature, created by man's selfishness", although it remained legal.[4]