Battle of Fredericia Day is observed in Denmark on July 6, commemorating the decisive battle of the First Schleswig War, also known as the Three Years’ War. This conflict marked the first military engagement between Denmark and Germany over the control of the duchies of Schleswig and Holstein. The battle took place in 1849 when Danish troops, under Colonel Lunding, launched a surprise attack against the besieging Schleswig-Holsteinian forces. The Danish victory at Fredericia was significant, leading to a truce that established separate governance for Schleswig and Holstein. As an official flag flying day in Denmark, the anniversary is marked by the display of flags, honoring the historical importance of the battle and its role in Denmark's eventual victory in the war.