Battle of Ahvenkoski

The Battle of Ahvenkoski was fought during the Finnish Civil War on April 10th - May 5th in 1918 at Ahvenkoski, Finland between the German Empire and the Finnish Socialist Workers' Republic also known as Red Finland. The battle was mostly trench warfare, with both parties settled at their positions by the Kymijoki river. Ahvenkoski and the surrounding Kymenlaakso region were the last strongholds of the Reds. The battle had finally ended with the last remaining Red Guards surrendering to the German troops on May 5, with Red Finland losing the war.

German campaign begins
Germany launched its military campaign in Southeast Finland on April 7th as the Detachment Brandenstein landed in Loviisa. Their goal was to take the coastal town of Kotka situated 40 kilometres east of Loviisa, then head north to the railway junction of Kouvola by the vital Saint Petersburg railway. The next morning, a 300-men reconnaissance unit reached the outskirts of Kotka, but was stopped in the Battle of Kyminlinna.

As the Germans waited for reinforcements, they tapped enemy telephone lines and mistakenly believed that the Reds had a reserve of 10,000–30,000 men heading to Kotka from the northern Kymenlaakso region. In reality, the Reds were strengthened by only 450 men. The German unit first retreated to Ahvenkoski, 20 kilometres east of Kotka. As they were soon followed by the Reds, Germans moved 8 kilometres further west, where they raised defensive positions by the Taasianjoki river. The Reds decided to stay in Ahvenkoski, where they equipped 18th-century fortifications by the Kymijoki river. They were soon joined by Reds, who had retreated from the Karelian Front.

Battle at Ahvenkoski
The next one and a half weeks were quiet, as the fighting was focused north of Loviisa in the Eastern Uusimaa region. On 22 April, the Germans marched to Ahvenkoski, and attacked the next morning. The battle went on for two days, but they were not able to break through the Red lines. On 25 April, the Reds left their positions in the western side of the Kymijoki river and retreated across the river, destroying the bridges on their way. The Germans occupied the western side of Kymijoki, and the battle now turned into a trench warfare for the next eight days.

The Reds soon found out that their front in Karelia had collapsed after the Battle of Vyborg on 29 April, and they had suffered a decisive loss in the Battle of Lahti too. This meant that Kymenlaakso area was now the last Red stronghold. A ceasefire was established in 3 May, and the parties started negotiation on the Red surrender.

Red Finland surrender
The Reds in Kymenlaakso started surrendering on 4 May, first in the village of Inkeroinen in Anjalankoski. In the same evening, the Whites entered Kotka, where 4,000 Reds surrendered without hardly any resistance. The last Reds left were now the 800–900 fighters in Ahvenkoski.

The negotiations in Ahvenkoski were mediated by foreign representatives based in Kotka. The Red delegation was led by Juho Kaven, a 24-year-old carpenter from Malmi, Helsinki. According to the agreement concluded with the Germans, the Reds would surrender their weapons by 5 May on 6 PM at the latest. The individual soldiers would then be released and only the leaders would be captured, although the Finnish Whites demanded an unconditional surrender.

The surrender began at midday of 5 May, as 800 Reds marched behind their staff commander Oskar Vinter towards the German lines on the western bank of the Kymijoki river. After crossing the Rajasilta Bridge, they surrendered their weapons. Despite the agreement, the Red fighters were not released, even though the Germans would have agreed to it. After capturing the Reds, the Whites separated the staff members, platoon leaders and trade union activists from the crowd, and took them to the Svartholm fortress, where they were immediately shot. The rest were kept overnight in the Vähä-Ahvenkoski village, and then transported to various prison camps in Southern Finland. In the following week, the Whites executed nearly 300 Reds in Kymenlaakso.

The Battle of Ahvenkoski ended the action of the Civil War, but the White Army commander C. G. E. Mannerheim did not declare the end of war until 16 May, when the Russians had left the Fort Ino near Petrograd.

Commemoration
Seven Germans were buried in the Ahvenkoski Cemetery, as well as an unclear number of Reds. The memorial on the Red mass grave was not erected until 1946. In September 2013, the memorial of the end of the Civil War was unveiled at the site where the last Reds surrendered.