Smuta
"The Livonian War and Time of Troubles:" Instead of consolidating his gains in the southeast, Ivan the Terrible turned west (Livonian War 1558–1583). After some initial successes, the war degenerated into a free-for-all among all the Baltic powers. At war's end, Russia returned, exhausted, to its original frontiers. The strain of this war, Ivan's erratic behavior, and other factors led to the Time of Troubles (1598–1613). This confusion led to a fair number of people to flee south of the Oka, but, as usual, we have no numbers.