Kaunas Fortress - World War I

World War I

In 1915, Germany and the Central Powers began an offensive against Russia and advanced towards Lithuania and Kaunas. The German army reached Kaunas Fortress in July 1915. At that time, about 90,000 soldiers, commanded by Vladimir Grigoriev (Russian: Владимир Григорьев), manned the fortress. To attack the fortress, the Germans brought four divisions to the operation, which were placed under the command of Karl Litzmann.

To support this attack, the Germans constructed a railroad to transport their 42-centimetre (17 in) Gamma-Gerät howitzer. The howitzer's shell weighed about 1 ton with a range of 14 km (8.7 mi). Several days into the siege more guns of various calibers were deployed.

The German army concentrated its attack on the First, Second and Third Forts, which were the complex's oldest structures. The army did not surround the entire fortress, and its defense was able to regroup and resupply. On August 8, the Germans intensified their bombardment, but the fortress garrison withstood several attempts to breach the defensive perimeter. Several days afterward, the bombardment of the fortress reached its peak; its defenders sustained heavy casualty rates of 50% to 75%. On August 14, over 1,000 defending troops were killed, but the Germans were unable to completely overcome the fortress' defenses. However, on the next day, Gamma-Gerät shells destroyed the First Fort and the Germans transferred their attentions to the Second Fort. The fight was now within the confines of the greater fortress complex.

At the cost of many casualties, the Third Fort's defenders delayed the advance of the Germans, but were forced to evacuate and retreat later the same day. The next day the Fourth Fort was abandoned and the Fifth Fort was conquered soon afterwards. In a chain reaction, the other forts began capitulating. Commander Grigoriev abandoned his post and escaped to Žiežmariai. When the Germans crossed the Nemunas river they captured the Sixth and Seventh Forts. The remaining two forts were captured soon afterwards. After eleven days of fighting, the fortress had been taken.

The defensive forces sustained 20,000 casualties, and about 1,300 weapons were captured by the Germans. Grigoriev was arrested by Russian authorities, tried, and sentenced to fifteen years in prison for failure to properly perform his duties. He also suffered the revocation of all his awards, military degrees, and honors. The Germans used materials from the fortress elsewhere during their war against Russia.

Researchers have identified factors contributing to the relatively rapid fall of the fortress. It had not been completely renovated; its defenders were inexperienced; the crew had been frequently rotated, and had not been able to familiarize themselves with the surrounding area and with the fortress. Although most of their experience lay in the defense of the fortress' interior, they were dispatched to fight on open ground. When the combat moved outside the fortress, communication lines were disrupted by the German bombardment, and the fortress defense was unable to restore complete communication with the command center or with other forts. The absence of external support was a crucial factor in its fall.