Which preposition to use with oratorian

of Occurrences 1%

I was strongly opposed both to his Ultramontane policy and to those dexterous methods by which he was commonly supposed to promote it; and, as far as the circumstances of my life had given me any insight into the interior of Romanism, I sympathized with the great Oratorian of Birmingham rather than with his brother-cardinal of Westminster.

Which preposition to use with  oratorian