In discussions on the whether Christianity played a key role in the abolition of slavery in the Western world, I've read the claim that the Christian Europe state, around 800-1000 AD, was the first place where slavery was abolished.
For example, commenter xlr wrote
Christian Europe in the post-Roman state was the first and for centuries only place on the planet were slavery was abolished. This was due to inherent issues between the faith and slavery.
Is this true?
EDIT: Since the initial answer refers to a place that 'abolished' slavery for three years before re-instating it, let's make this interesting and ask if Christian Europe was the first place to abolish slavery for a long period of time - say 100 years?