By this time, the Kazan icon had achieved immense popularity, and there were nine or ten separate miracle-working copies of the icon around the country. There is considerable disagreement about which, if any, of these was the original. Some claim the original remained housed in Kazan, while others hold that the one moved from Moscow to St. Petersburg was the original. Many experts, however, believe the original was lost and both of the venerated Kazan icons were early copies. In any case, both icons disappeared in the early 20th century. The one in Kazan was stolen in 1904 and probably destroyed by the thieves, who were more interested in its jeweled gold covering. The one in St. Petersburg disappeared after the October Revolution of 1917. Some say it was smuggled out of the country to protect it from the Bolsheviks, while others suggest the Communists themselves hid it and later sold it abroad. But during World War II, an icon of the Virgin of Kazan surfaced in Leningrad to lead a procession around the fortifications of the Nazi-besieged city.

== Liturgical Hymns ==