Flag of Germany
When Heinrich XI, Prince Reuss of Greiz was appointed by Joseph II, Holy Roman Emperor to rule the then-new Principality of Reuss-Greiz on 12 May 1778, the flag adopted by the "Fürstentum Reuß-Greiz" was the first-ever appearance of the black-red-gold tricolour in its modern arrangement in any sovereign state within what today comprises Germany – the Reuss elder line that ruled the principality used a flag whose proportions were close to a "nearly square"-shape 4:5 hoist/fly ratio, instead of the modern German flag's 3:5 figure.
List of flags of the German Navy (1935–1945)
The Reichskriegsflagge, which was introduced on 7 November 1935, was widely used in the Wehrmacht. Thus, it also served the Kriegsmarine as the naval ensign, which was hoisted on Flag days regardless of the location of the ship. These were the 1 January (New year), the 18 January (founding day of the Empire 1871), the 30 January ("day of national survey"), the 20 April (Hitler's birthday), the 1 May ("Labor Day") and 31 May (memory of the Battle of Jutland). In addition, ships in home waters, had to hoist the Reichskriegsflagge on these following days: on 1 March (reintegration of the Saarland), on 29 August (the day of the founding of the Prussian Navy in 1859), on the first Sunday after Michaelmas and on the day of the Harvest festival. Regardless of these days, all warships that received a head of state were obliged to show the Reichskriegsflagge.