The Cathedral of the Theotokos in Vilnius is the main Orthodox Christian church of Lithuania. The cathedral was built during the reign of the Grand Duke Algirdas in 1346. It was constructed by Kievan architects with the blessing of Saint Alexius Metropolitan of Kiev and all Rus in 1348. The Cathedral of the Theotokos is one of the most ancient churches of Vilnius, built before the christianization of Lithuania when the Grand Duchy of Lithuania was the last pagan state in Europe. It became an important spiritual centre for the growing Christian population of the duchy. In 1495 the marriage between Aleksandras of Lithuania and Yelena of Muscovy (Ivan III's daughter) was held in the cathedral in the presence of Saint Macarius. It was there that Yelena was buried in 1513. After the conversion of Lithuania to Roman Catholicism, the Orthodox cathedral was protected by princes Konstanty Ostrogski and Konstanty Wasyl Ostrogski, who restored it after the collapse of the dome in 1506. After their deaths, the cathedral was taken over by the Greek-Catholic church in 1609 and was rebuilt in a style typical of the region. In 1748 the cathedral was abandoned after a major fire and the building was used for various other purposes. It was reconstructed in the Baroque style in 1785. The cathedral was once again destroyed by Russian army during the Kościuszko Uprising. In 1808 a local prelate sold the neglected building to the Vilnius University, which had the building thoroughly modernised in 1822 in the Neoclassical style by Karol Podczaszyński. After that, the building hosted an anatomical theatre, library and other university facilities for half a century. The old Orthodox cathedral was confiscated and transferred to the Russian Orthodox Church on the initiative of count Mikhail Nikolayevich Muravyov and his brother during the Russification campaign. The Russian architect Nikolai Chagin was responsible for its reconstruction from 1865 until 1868 in a style imitating medieval Georgian architecture. Why such a style was applied is not clear. St. Tikhon (Belavin), then Archbishop of Vilnius, presided over the cathedral and Orthodox Christians of Lithuania between 1913 and the occupation of Lithuania by the German troops in 1915. Most of the Russian Orthodox clergy left with the retreating Russian army. The cathedral of the Theotokos was damaged during the Second World War but was restored in 1948, although its renovations were not completed until 1957. Today the cathedral belongs to the Russian Orthodox Church and was once again renovated in 1998. Its services are attended mostly by ethnic Russian and Belarusian residents of Vilnius. http://en.wikipedia.org/wiki/Cathedral_of_the_Theotokos,_Vilnius