 Italy was the site of several key musical developments in the development of the Christian liturgies in the West.Around 230, well before Christianity was legalized, the "Apostolic Tradition" of Hippolytus attested the singing of Psalms with refrains of Alleluia in Rome.In 386, in imitation of Eastern models, St. Ambrose wrote hymns, some of whose texts still survive, and introduced antiphonal psalmody to the West.