After Russian penal law changed in 1847, exile and penal labor ("katorga") became common penalties for participants in national uprisings within the Russian Empire. This led to sending an increasing number of Poles to Siberia for "katorga", when they then became known as "Sybiraks". Some of them remained there, forming a Polish minority in Siberia. Most of them came from the participants and supporters of the November Uprising of 1830-1831 and of the January Uprising of 1863–1864, from the participants of the 1905-1907 unrest and from the hundreds of thousands of people deported as a result of the Soviet invasion of Poland in 1939.