The Church of Jesus in Cieszyn is the largest Protestant church in Poland. Its huge silhouette dominates the landscape of the city. The construction of the church by the Protestants, who so far had been persecuted, was made possible by the Altranstädter convention f 1707. Thanks to the convention, the Austrian Emperor Joseph I authorized the erection of the six so-called “mercy churches”. From the outside, the church was built in the Austrian Baroque style, and it resembles the Catholic churches, but the interior reflects the spirit of the Reformed faith.