Translation: “Germany is victorious on all fronts”. The V stands for Victory. The Allied V-for-Victory cliché became so popular as a morale raiser that the enemy had to adopt to it, an easier task for the Italians, whose Vs displayed in public could be held to stand for Vinceremos, or We Will Win, than for the Germans, embarrassed by the fact that properly their V for Victory should be S for Sieg. The propaganda officers just changed Sieg to Viktoria, alluding to the “Germano-Latin” tradition. They said the use of V’s by civilians was a sign of support for Germany. They just used Viktoria because it had to start with V, and the V originally meant
“V for victory” when Churchill used it, so they probably needed something similar in order to not make it too obvious. When the Germans started their campaign, Churchill noted that they probably meant “verloren”, German for defeat. The French resistance would often alter one letter to these type of banners and the message was transformed to Deutschland Liegt auf allen Fronten – Germans lie on every frontline.