The Cossacks refer to a group of Eastern and Asian Europeans. They are most well known as effective soldiers who patrolled the Russian borders. They are also famed for their injustices against Jews that ultimately led to the Jewish exile from Russia prior to the Russian Revolution.
Early groupings of Cossacks were slightly nomadic and always constructed along military lines. They answered to a high military leader called an ataman. Laws were not written but everyone within a Cossack group, including clergy would answer to the ataman.
In fact, the Cossack groups are well known for their close ties to the Russian Orthodox Church. A minority of Cossacks, however, may have been Muslim, or have been of a different Christian orientation. However, generally, most Cossacks were supporters of the Orthodox Church, which gave the Orthodox church much power.
The Cossacks also had power since they often formed cavalry units, and early used horses to participate in battles. They played important roles in repelling the French forces during the Napoleonic Wars.
The race of Cossacks split into different holdings in Eastern Europe, and some groups intermarried with other local races. Others married within their own ethnic group, and were thought prejudiced against different ethnicities. This was particularly the case with the Jews, who were persecuted without end by Cossack troops.
Given the religious stance of the Cossacks, it was hugely surprising that they did not support Tsarist Russia and actually joined the revolution to overthrow the Tsar in 1917. As such, many of the Cossacks became more integrated in the society that followed, and as well, abandoned their religions in droves.
With the end of communism in the Soviet Union, many descendants of the Cossacks have shown an interest in examining the life and culture of Cossacks. They now have once again become part of the armies belonging to the countries into which the Soviet Union split. Army designations are based on the old designations of the Cossacks, and the descendants of the Cossacks are now honored for their past organizations and as noble members of the military.