Complex sentence: During this last period he Dean of the Chapel Royal, a Royal Household office, for which he was appointed Knight Commander of the Royal Victorian Order (KCVO), and was also Prelate of the Order of the British Empire.
Split into simpler sentences: During this last period he Dean of the Chapel Royal, a Royal Household office, for which he was appointed Knight Commander of the Royal Victorian Order (KCVO). He was also Prelate of the Order of the British Empire.