With the baptism of the Grand Prince
Vladimir the Great and the
Christianization of the
Kievan Rus', the region's architecture became heavily influenced by
Byzantine architecture. During the 13th century and start of 14th century, the Slavic principalities are eventually subjugated by the
Grand Duchy of Lithuania, a pagan state which was
fighting against the
Teutonic Order's expansion. The Grand Duchy became a dominant power in the 14th century, featuring a developed
Lithuanian nobility. Lithuanian rulers started building
Brick Gothic castles and establishing
Catholic churches, which were also constructed in Brick Gothic. Contacts with the Teutonic order and Europe allowed to hire experienced
architects. The
Act of Krėva in 1386 caused the
Christianization of Lithuania and increased communication in western and southern Europe. Christianization of Lithuania led to more intensive expansion of
Western culture and namely,
Gothic style into Orthodox lands. During this period, the
Gothic style came to the Slavic regions. In central and southern Europe however, it was already being displaced by
Renaissance architecture. In 1346 the Orthodox
Cathedral of the Theotokos, Vilnius in
Vilnius, was constructed, before the Lithuanian state had become Catholic. (see
history of Roman Catholic Lithuania). File:20090613 003 Наваградак (39).JPG|alt=Side of a white church|Cathedral of Ss. Boris and Gleb,
Navahrudak (1519–1630), southern façade File:Церква Святих Бориса і Гліба в Новогрудку.jpg|alt=Church interior with high, vaulted ceilings|Ss. Boris and Gleb interior (1930 photo) File:Hniezna. Гнезна (2007).jpg|alt=Church exterior against a blue sky|Church of Saint Michael,
Hniezna, 1524–1527 File:Belarus Mir Mir Castle Complex 8112 2100.jpg|alt=Large building against a partly-cloudy sky|The 16th-century
Mir Castle File:Orthodox Cathedral of the Dormition of the Theotokos 2, Vilnius, Lithuania - Diliff.jpg|alt=Church interior with icons|
Cathedral of the Dormition of the Theotokos,
Vilnius File:Suprasl orthodox church 3.jpeg|Church of
Supraśl Orthodox Monastery,
Poland File:Kodeń church1.JPG|alt=Simple brick Gothic church|Church of the Holy Ghost (1530) in
Kodeń, Poland, near the
Bug River File:Траецкі касьцёл у Ішкальдзі, 1472 год.jpg| in File:Vilnia, Trajeckaja. Вільня, Траецкая (J. Bułhak, 1917).jpg|
Greek Catholic Church of Holy Trinity in
Vilnius File:Murovanka church.jpg|
Church of the Nativity of the Blessed Virgin Mary in
Muravanka File:Царква ў Мураванцы. Гатычныя скляпенні.jpg|Church in
Muravanka == Architecture ==