Ó Ceallaigh's strong Roman Catholic beliefs sometimes caused problems. de Valera often thought that Ó Ceallaigh either deliberately or accidentally leaked information to the Knights of Columbanus, and the Church leaders. Ó Ceallaigh ensured that his first state visit, following the creation of the Republic of Ireland in 1949, was to the Vatican to meet Pope Pius XII. Ó Ceallaigh accidentally revealed the Pope's private views on communism. This angered the Pope and Stalin. This is why he was not given the papal Order of Christ which was given to many Catholic heads of state.