Foch Line

The Foch Line was a proposed demarcation line between Poland and Lithuania after World War I, suggested by Marshal Ferdinand Foch of France. It was intended to serve as a temporary border, allowing for a plebiscite to determine the final territorial boundaries.

Two versions of the Foch Line were proposed, both differing significantly. The first version, proposed in July 1919, heavily favored Poland, leaving Vilnius (Wilno in Polish) and its surrounding region under Polish control. This line was largely based on ethnic considerations, attempting to allocate areas with a Polish majority to Poland and areas with a Lithuanian majority to Lithuania.

However, due to ongoing conflicts and shifting political circumstances, a second, modified Foch Line was presented in December 1919. This later version was more favorable to Lithuania, assigning Vilnius and a wider surrounding territory to Lithuania. The primary motivation for the shift was to reduce tensions and potentially achieve a negotiated settlement. This second version also considered the historical importance of Vilnius to Lithuanian culture and identity.

Neither version of the Foch Line was ever fully implemented or accepted by both parties. Poland, having already seized Vilnius in 1920 during the Polish-Lithuanian War, never relinquished control. The issue of Vilnius remained a significant point of contention between Poland and Lithuania throughout the interwar period, with Lithuania refusing to recognize Polish sovereignty over the city. The final border was only definitively established after World War II. The Foch Line is thus remembered as a significant, but ultimately unrealized, attempt at mediating the territorial disputes between Poland and Lithuania following the collapse of the Russian Empire.