Germany
The earliest reports of Germanic militia was the system of hundreds which was described in 98 A.D. by Tacitus as the centeni. It was similar to the Anglo-Saxon fyrd.
The name Freikorps (German for "Free Corps") was originally applied to voluntary armies. The first freikorps were recruited by Frederick II of Prussia during the Seven Years' War. The freikorps were regarded as unreliable by regular armies, so that they were mainly used as sentries and for minor duties.
However, after 1918, the term was used for nationalist paramilitary organizations that sprang up around Germany as soldiers returned in defeat from World War I. They were one of the many Weimar paramilitary groups active during that time. They received considerable support from Gustav Noske, the German Defence Minister who used them to crush the Spartakist League with enormous violence, including the murders of Karl Liebknecht and Rosa Luxemburg on January 15, 1919. They were also used to put down the Bavarian Soviet Republic in 1919. They were officially "disbanded" in 1920, resulting in the ill-fated Kapp Putsch in March 1920.
The Einwohnerwehr, active in Germany from 1919 to 1921 as a paramilitary citizens' militia consisting of hundreds of thousands of mostly former servicemen. Formed by the Prussian Ministry of the Interior on April 15, 1919, for the purpose to allow citizens to protect themselves from looters, armed gangs, and revolutionaries. The Einwohnerwehr was under the command of the local Reichswehr regiments and which supplied its guns. In 1921, the Berlin government dissolved the Einwohnerwehr. Many of its members went on to join the Nazi Party.
In 1944-45, as World War II was coming to a close in Europe the German high command deployed increasing numbers of Volkssturm units to combat duties. These regiments were composed of men and women too old or otherwise unfit for service in the Wehrmacht (German Regular Army). Their primary role was assisting the army with fortification duties and digging anti-tank ditches, but would as the shortage of manpower became severe be used as front line infantry, most often in urban settings. Due to the physical state of members, almost non-existent training and shortage of weapons, there was not much the Volkssturm could do except act like shields for regular army units. However, armed with Panzerfausts and deeply entrenched a unit of Volkssturm could cause serious trouble for Soviet armor.
Read more about this topic: Militia