Between 18 and 22 September 1917, he participated in the Lithuanian Conference in Vilnius, and was elected Chairman (1917–1919) of the Council of Lithuania (later Council of the State).
Mellem den 18. og 22. september 1917 deltog han i den litauiske konference i Vilnius, og blev valgt som formand (1917-1919) for Det litauiske nationalråd (senere Statens Nationalråd).