Ukrainian architecture has initial roots in the Eastern Slavic state of Kievan Rus'. After the Mongol invasion of Kievan Rus', the distinct architectural history continued in the principalities of Galicia-Volhynia and later in the Grand Duchy of Lithuania. During the epoch of the Zaporozhian Cossacks, a style unique to Ukraine developed under the influences of the Polish–Lithuanian Commonwealth. After the union with the Tsardom of Russia, architecture in Ukraine began to develop in different directions, with many structures in the larger eastern, Russian-ruled area built in the styles of Russian architecture of that period, whilst the western Galicia was developed under Austro-Hungarian architectural influences, in both cases producing fine examples. Ukrainian national motifs would eventually be used during the period of the Soviet Union and in modern independent Ukraine. Source: Wikipedia (en)