the quality of their weapons and war industry, face a force of 370,000 Austro-Russian forces, and other tens of thousands of Croatian, Serbian and Romanian insurgents, who serve the Habsburg imperial interests. June 20 – Hungarian Revolution of 1848: Russian troops, under the command of Alexander von Lüders, break in Transylvania, and, together with the Austrian forces, start to operate against the Hungarian troops, led by Józef Bem. June 21 – Hungarian Revolution of 1848: The Russo-Austrian army, led by Julius Jacob von Haynau, defeats the Hungarians under the command of Arthur Görgey at Pered. June 28 – Hungarian Revolution of 1848: The Austrian army, led by Julius Jacob von Haynau, defeats the Hungarians, led by Ernő Poeltenberg, at Győr. The Hungarian army is forced to retreat towards Budapest. July–September July 2 – Hungarian Revolution of 1848 – Second Battle of Komárom: The Hungarian army, led by Arthur Görgey, repulses the combined attack of the Austrian and Russian troops led by Julius Jacob von Haynau. During the battle Görgey suffers a heavy head injury, which prevents him from taking advantage of this success. July 3 – French troops occupy Rome; the Roman Republic surrenders. July 6 – Battle of Fredericia: The Danish Army beats the Prussian army at Fredericia, Jutland, thereby putting an end to the Prussian-Danish War until 1864. July 11 – Hungarian Revolution of 1848 – Third Battle of Komárom: The Hungarian army, led by Arthur Görgey, is defeated by the Austrians, led by Julius Jacob von Haynau. July 14 Hungarian Revolution of 1848: Because of the imminent Austrian attack, the Hungarian government moves from Budapest to Szeged. Hungarian Revolution of 1848: Hungarian troops, led by Richard Guyon, defeat the Croatian-Austrian army led by Josip Jelačić at Kishegyes, securing southern Hungary for the revolutionary government. July 17 – Hungarian Revolution of 1848: Hungarians, led by Arthur Görgey, and the Russians, led by Ivan Paskevich, battle indecisively at Vác. The Russians are unsuccessful in destroying the Hungarian army, which retreats towards the east. July 23 – The French scientist Hippolyte Fizeau measures the speed of light, with an instrument placed on the Earth. July 28 – Hungarian Revolution of 1848: The Hungarian government, led by Bertalan Szemere promulgates the Nationality Law, which gives important rights to the nationalities of Hungary, like the right to use their mother tongue in school, church, army, court and administration. The Romanians are declared