The Baltic countries, like Poland, have a history of being walked over by marauding armies. Nevertheless, the people kept their own language of Fenno-Ugric family - mainly Estonian, Finnish, Hungarian, and a number of close to extinguished smaller languages in various areas what is now Russia.
Part of Russian Empire after Sweden convincingly lost her status as an empire after Great Northern War, Estonia declared her independence after Bolshevik revolution in 1918, fough Red Army, and made peace with bolshevik Russia ie Soviet Union in 1920.
Given to Russia in the infamous Molotov-Ribbentrop treaty, Germany withdrew Estonians german speaking population, before Stalin first demanded military bases, then forced a fixed election with bolshevik candidates only, and with a vote of 99% annexed Estonia into Soviet Union.
A typical terror started: intelligentsia (educated people), kulaks (anyone owning land), were shot or sent to prison camps, anyone suspectible of not being a proper homo sovieticus transported to Siberia labour camps.
Soon after, Red Army started to force Estonian men into Red Army, and the underground Estonian organization was loosely starting to take shape as men hid from Russians.
When Barbarossa begun, some action were taken to assist Germans in routing the Red Army from Estonia. Dreams for an independent Estonia very soon died, holocaust first really raised its ugly head in the Baltics as practically all Baltic jews were murdered.
Germans soon started to enlist Estonians to German army, but again the Estonian underground and people refused to participate. Only in 1944, when it was obvious Red Army is at the gates of Estonia again, volunteers started to join German army, especially as this time they got to serve in Estonia.
The plan was to organise a free Estonia once the Germans were gone and before Red Army would be in, with the assumed support of Western powers. This never got to take place, US and UK were of course not interested in this small region to make talks with Stalin due to fighting and destroying Nazies.
After Soviet terror came Nazi terror, again replaced by Soviet terror, both regimes ruthlessly killing their assumed enemies. The Forest Brothers organization fought the Soviet occupation until well into 1950s, waiting for the presumably unevitable WW III against Soviet Union that (luckily for the rest of world!) never came.
I recommend watching the document, it is very matter-of-fact, non-biased with interviews from both sides.
And a disclaimer to Estonian history lesson, I'm a Finn, not an Estonian. I expect to be corrected by an Estonian as well :)
EDIT: I just realised it is exactly 20 years ago today that Estonia broke her Soviet shackles again, in August 20 1991.
Happy birthday independent Estonia!!!