In the 16th century, a church dedicated to the Virgin Mary was erected in the courtyard of the Brzeżany castle, founded by Adam Hieronim Sieniawski. The church, richly decorated and furnished with numerous works of art, over time became the Sieniawski family mausoleum, considered, along with the collegiate church in Żółkwi, to be one of the most important in the lands of the former Commonwealth. After the death of the last representative of the Sieniawski family, the building began to deteriorate. However, the unique tin sarcophagi survived the collapse of the vault and were later saved from the Bolshevik invasion in 1920 and taken to Poland. Also partially preserved are the sculptures from the tombstones, which were taken to the storage facilities of the Lviv National Art Gallery after World War II.