During the plague epidemic of 1713, Emperor Charles VI vowed to build a church dedicated to St Carlo Borromeo, the plague saint. The Emperor made this monumentally conceived votive building an affair of state, to which all Habsburg lands had to contribute financially. Johann Bernhard Fischer von Erlach's design, with an oval plan behind a wide facade, was adopted. The church was begun in 1716 and completed in 1737; Joseph Emanuel Fischer von Erlach continued the work after his father's death in 1723 and was probably responsible for changes in the executed work (notably the increase in the height of the drum). The facade of the Karlskirche, intended to be viewed from a distance, faces the Hofburg. Its Corinthian portico, flanked by two colossal columns and two gateway tower pavilions, is dominated by the tall oval drum and dome rising behind it. In this context the two colossal columns of the Karlskirche should be seen as an appropriation of the triumphal columns of Trajan and Marcus Aurelius in Rome, symbolizing imperial aspirations.