On 20 January, 1842, while waiting for a friend in one of Rome's old churches, a young Jewish gentleman, Alphonse Ratisbonne, was miraculously converted from disbelief in any religion to a fervent and lasting Catholicism when he experienced an apparition of the Virgin Mary. It caused a great stir in Rome, and crowds turned out to witness the young man's baptism. This is an entirely new translation from the French of Conversion de M. M-A Ratisbonne, (Second Edition, 1842), which includes Ratisbonne's own dramatic narrative. It is a compelling read, not only for Roman Catholics, but for all those interested in the phenomena of religious conversion.