Badge of the <a href="https://en.wikipedia.org/wiki/Democratic_Army_of_Greece" class="extiw" title="w:Democratic Army of Greece">Democratic Army of Greece</a>, which fought in the <a href="https://en.wikipedia.org/wiki/Greek_Civil_War" class="extiw" title="w:Greek Civil War">Greek Civil War</a> of 1946-1949. The blue and white colours derive from the Greek flag, the letter Delta stands for Δημοκρατία, which means both "Democracy" and "Republic" in Greek.
<a href="//commons.wikimedia.org/wiki/User:Cplakidas" title="User:Cplakidas">Constantine</a>
Own work based on: <a href="//commons.wikimedia.org/wiki/File:DSE_%CE%94%CE%A3%CE%95_symbol.JPG" title="File:DSE ΔΣΕ symbol.JPG">DSE ΔΣΕ symbol.JPG</a> <i>by</i> <a href="//commons.wikimedia.org/wiki/User:Dimkoa" title="User:Dimkoa">Dimkoa</a>