 Complete the following phrase:  In 1038, Kraków became the seat of the Polish government. By the end of the 10th century, the city was a leading centre of trade. Brick buildings were constructed, including the Royal Wawel Castle with St. Felix and Adaukt Rotunda, Romanesque churches such as St. Adalberts, a cathedral, and a basilica. The city was sacked and burned during the 