Complex sentence: The hotel was named not after Randolph Churchill, who was connected with Blenheim Palace to the north of Oxford, but because it was near the Randolph Gallery in the new Ashmolean Museum opposite.
Split into simpler sentences: The hotel was not named after Randolph Churchill (who was connected with Blenheim Palace to the north of Oxford). Rather it was because it was near to the Randolph Gallery in the new Ashmolean Museum opposite.