The beginning of the Croatian written language can be traced to the 9th century, when Old Church Slavonic was adopted as the language of the Divine liturgy of St. John Chrysostom and the Divine Liturgy of Saint Basil. This language was gradually adapted to non-liturgical purposes and became known as the Croatian version of Old Slavonic. The two variants of the language, liturgical and non-liturgical, continued to be a part of the Glagolitic service as late as the middle of the 19th century. The earliest known Croatian Church Slavonic Glagolitic are "Vienna Folios" from the late 11th/early 12th century. Until the end of the 11th century Croatian medieval texts were written in three scripts: Latin, Glagolitic, and Croatian Cyrillic ("bosančica/bosanica"), and also in three languages: Croatian, Latin and Old Slavonic. The latter developed into what is referred to as the Croatian variant of Church Slavonic between the 12th and 16th centuries.