 Complete the following phrase:  The beginning of the 17th century proved to be a troublesome period for the Moscow state, following the death of the last Tsar of the Rurik Dynasty, Feodor Ivanovich, in 1598. The Poles and Swedes repeatedly invaded Russia from the west, with the Polish prince Władysław Vasa elected the Russian Tsar by the Seven Boyars in 1610. At this time of political turmoil, Patriarch Germogen 16061612, proved to be a staunch opponent of the Seven Boyars as well as any Catholic pretender to the Moscow throne. That period also saw the Trinity Monastery the modern Trinity Lavra of St. Sergius withstanding months of a 