Siberia has the largest Lutheran church (geographic area)

According to Thrivent Magazine, Fall 2011, p. 8, the largest Lutheran church in the world (geographically) is the Siberian Evangelical Lutheran Church, Сибирская Евангелическо-Лютеранская Церковь. Founded in the 1990s, this organization has 13 ordained pastors and deacons who serve roughly 1,000 members in congregations and missions across 6 time zones in a 3,000 mile area. (Thrivent magazine) I'm wondering if this is part of the Lutheran group they discovered after the break up of the USSR made up of descendants of German POWs of WWI who never got back to Germany and intermarried with the Siberian women. The liturgy was in German but none of the members any longer spoke German.