I think most people with a passing knowledge of the soviets in WW2 are aware of the russian commisars who stood behind the lines of the advancing troops and opened fired on retreating troops. how prevalent was this across the entire soviet army? Was it at all engagments?
When did this start as well? Was this introduced from the beginning? or after some major losses in the early days?
As an add on, what exactly was a commisar? I've heard them refered to as political officers, so am I right in guessing they were trying to uphold soviet or stalinist values in troops?
Although this image of Soviet soldiers being shot at from both sides is an incredibly popular one, it is more myth than fact. /u/Georgy_K_Zhukov has written many fine posts on this, including this post of theirs which distinguishes between barrier troops, levies, and the regular Red Army. As for commissars, this answer of mine outlines their wartime and postwar functions.
Always more that can be said, but you'll likely find this old thread to be relevant.