[@Oak7ree] This is the battle of Tali-Ihantala in Finland. If you look closely to the uniform, you'd notice it's actually Finnish. When USSR attacked Finland, Finland became allies with Germany, and many things (including soldiers, I think) were sent to Finland to help them out.

Germany saw Finland as a crucial ally, especially because of Leningrad (USSR attacked Finland because the border was too close to Leningrad in the first place).