In 1869, he moved to Rome, where he served as
Cameriere (a Chamberlain of Honour) to
Pope Pius IX. The Cameriere wore a Spanish-style costume with cape and sword and had the duty of attending upon the pope during ecclesiastical and state functions. With his love of ritual Grissell relished life at the papal court. Writing in later life he reminisced: The temporal power of the pope ended in 1870, when
Victor Emmanuel II seized Rome, but Grissell continued to serve under
Pius IX and his two immediate successors,
Leo XIII and
Pius X. He was rewarded for his service by being created a Knight Commander of the
Order of St. Gregory the Great and, in 1898, one of the four
Papal Chamberlains
di numero, an honour usually reserved to the Roman nobility. Writing from Rome in 1900,
Oscar Wilde referred to Grissell as a stalwart of the conservative Papal Court: Whilst residing in Rome Grissell amassed a vast collection of relics and sacred curios, including a portion of the
Crown of Thorns and the entire body of St. Pacificus. The centrepiece of the collection was the reputedly miraculous image of the Madonna called 'Mater Misericordia' (now housed in the
Oxford Oratory and popularly known as 'Our Lady of Oxford'), to which Pius IX granted indulgences at Grissell's request. Besides being an expert in matters liturgical, Grissell was a noted numismatician and was elected to a fellowship of the
Society of Antiquaries of London. For
Oscar Wilde, Grissell was merely "the withered eunuch of the Vatican Latrines". ==Newman Society==