The fortress of Kaunas was one of the strongest land fortresses of the Russian Empire at the end of the XIXth - the beginning of the XXth century. At the beginning of World War I, Kaunas passenger and merchant ships were passed over to the staff of the Kaunas fortress. The army coated two steamboats - the "Jaroslavna" and the "Venera" [Venus] - with armourplates and armed them. On the 13th of May, 1915, the steamboat "Jaroslavna" took part in the battle with the German army, and the "Venera" steamboat joined the battle soon after. With respect to individual missions, the participation of such steamboats in the defence of Kaunas fortress in 1915 often yielded positive results. In the Lithuanian military history this was the only case when armed steamboats took part in the battles on the Nemunas River.

Kaunas city was an important strategic point in the Western Russian Empire. At the end of the 19th and beginning of the 20th century, the city became a first-class military fortress, and it was the most important strategic military object. When World War I started in 1914, the German troops had to occupy the fortresses situated on the Western Russian border, including Kaunas, in order to have a successful offensive of the German troops on the Eastern Front. In June 1915, the plans to attack Kaunas Fortress were discussed. After the initial success of the Spring Offensive and the information from the intelligence service about the weakening of the enemy, the attacks started. Because of these circumstances, K. Litzmann, commander of the XL Reserve Corps, assembled the heavy artillery of the 10th Army near the Kaunas Fortress and started the offensive from the south-west. It was considered that massed artillery fire would demolish fortifications, disorder garrison and create great possibilities for the infantrymen attack. The Army did not need a considerable number of soldiers to enclose the fortress. On April 25, P. Hinderburg, the Commander of the Eastern Front, gave the order to start preparations for the offensive of Kaunas Fortress led by K. Litzmann. E. Falkenhayn, the Chief of General Staff, did not accept this sequence of military operations. The summer was over and the autumn has begun; therefore, it was necessary to start the offensive of Kaunas Fortress. The commanders of the Eastern Front decided to not defer it. On the night of July 19, the attack of XL Reserve Corps started in order to break the anterior fortifications of Kaunas Fortress without the consent of the German Emperor and the Commander of the General Staff.