Conversation so far:
Why was Richard III of England's reburial necessary?
As a condition of being allowed to disinter the skeleton, the archaeologists agreed that, if Richard III of England were found, his remains would be reburied in Leicester Cathedral.
Where were the remains of Richard III of England buried before reburial?
Richard III of England's remains were initially buried at Greyfriars Church in Leicester.

Question: Why was his body dug up?
Self-contained rewrite: Why was Richard III of England's body dug up?