The Battle of Gera was a major battle during the First German Civil War. The battle was an effect of Austria's promises to assist Mexico in their war against the United States in the hopes of gaining a trans-Atlantic colonial empire. The Pro-American Prussia and her allies, loosely coordinated into the North German Confederation, entered the Mexican-American War on the latter's side with the intent of keeping Austria from interfering militarily.
Graf Hans von Zieten, who was at the time commander of the 3rd Army based in southern Brandenburg, took the initiative by organizing and reinforcing his minuscule 33,000 men into an efficient fighting force of nearly 90,000 Prussian troops gathered from the garrisons at nearby cities and detachments from the nearby 2nd Army bordering northern Bavaria.
According to intelligence reports from spies and saboteurs within northwestern Bohemia, a combined Austrian-Saxon army of virtually 150,000 was preparing to march on Prussian territory and confront any troops they faced. Heavily outnumbered, von Zieten knew he would not have such luck that Frederick the Great had had against inferiorly equipped and led Austrian troops, and knew only numbers could solidify his chance of success. Soon another 55,000 north German troops arrived to bolster his already large army, and he began the march to northern Saxony. On August 9 his cavalry covering force spotted the bulk of the Austrian army approaching from an east-south-east heading and von Zieten organized the troops for battle.
Initial moves included the attack of the German uhlans and lancers on the Austrian right, which devastated the light infantry guarding the flank until their own Saxon heavy cavalry could mount a counterattack to drive them off. Shortly afterward the Prussian line infantry began moving to face the Austrian center which was held primarily by their own elite Foot Guard, many of which were of nobility or were wealthy merchants or landowners. The first Prussian attack was repulsed, which was followed by a countercharge from Bavarian infantry on the Austrian left. This was repulsed with the help of Hanoverian light infantry aided by the close-range fire of Prussian canister shot, which devastated the Federation's attack in this sector and forced them onto the defensive.