The Litany of the Blessed Virgin Mary is a Marian litany originally approved in 1587 by Pope Sixtus V. It is also known as the Litany of Loreto, for its first-known place of origin, the Shrine of Our Lady of Loreto (Italy), where its usage was recorded as early as 1558.
[...] Despite the fact that, from the seventeenth century onwards, the Litany of Loreto has been the subject of endless panegyrics and ascetical writings, there is a great lack of documentary evidence concerning its origin, the growth and development of the litany into the forms under which we know it, and as it was for the first time definitely approved by the Catholic Church in the year 1587. Some writers declare that they know nothing of its origin and history; others, on the contrary, trace it back to the translation of the Holy House (1294); others, to Pope Sergius I (687); others, again, to Gregory the Great or to the 5th century; while others go as far back as the earliest ages of the Church, and even Apostolic times. Historical criticism posits it to have been composed during the early years of the 16th century or the closing years of the 15th.
The most ancient printed copy hitherto discovered is that of Dillingen in Germany, dating from 1558; it is fairly certain that this is a copy of an earlier, but, by the time of writing of the Catholic Encyclopedia, the oldest known Italian copy dates from 1576.