When you flee from a wolf, you run into a bear
The Conquest of Finland
The shelling of Viipuri
For several months Finnish intelligence had taken note and with growing concern listed the build up of Russian forces along their border from the Gulf of Finland right up too the Arctic circle. Relations between the two powers had never been anything more than hostile, Russia grudgingly accepted Finnish ''sovereignty'' under terms from the German interventionist forces but crucially Russia never relented to accept Finnish independence. In return the Finnish kingdom considered and annexed the Karelia during the civil war, over the years since Finland took control the Russian population had dropped severely via expulsions conducted by the Finns. By early March 125,000 Finns under arms or around 80% of the Finnish military faced over a million Russians across the Karelian border.
Finnish troops advance to the border
While the question of Russian positions on Finnish independence was ambiguous, the position on Karelia was not. Russian policy for years had been to dispute Finnish ownership of the Karelia and to challenge at every possible opportunity. The strategic position of Karelia was great for Russia, Finnish neutrality couldn't be counted on, as a hostile power they could shell Saint Petersburg with heavy artillery from the border and the fear of a strengthened enemy aligned Finland could take the city in an invasion down the Isthmus and into wider Ingria, with the Russian government convinced that who ever wins the war in Europe will invade in the west, they needed breathing space and security in the North. As such the Russians managed to bring the Finns to the table to negotiate the future of Karelia a conference hosted by the Polish. The Krakow conference began on March 1st amid a gloomy atmosphere in Finland that war was likely, the Russians refused to debate the issue of Karelia and demanded its handover, the Finns went as far as to concede a plebiscite, however the expulsions of Russians over the years would have resulted in an anti Russian vote. The Russian attitude in the talks exasperated and insulted the Finns and ever the Polish mediators, a Russian diplomat had become drunk on one of the nights of the discussions and insinuated that the Polish themselves were living on borrowed time till Russia came to reclaim its domain. In Finland it became clear that the talks would fail and the Russians would soon cross the border, Helsinki instructed delegation to buy them as much time as they could as general mobilisation and preparations were made to prepare for the eventual Russian assault.
Helsinki prepares fearing Russian bombers will destroy the city
By the 9th the Russians had figured out the Finns game and had placed their forces on alert and issued their final terms to the Finnish delegation in krakow, ''Surrender Karelia to the Russian Empire or face punitive military action'', the Finns refused to budge and by midnight the Russians delivered a declaration of war upon the Finns.
So began the Summer war
For 8 hours from midnight on the 9th till morning on the 10th of March, Russian artillery subjected the Finish border forces to a ferocious battering. The Finns managed to hit Saint Petersburg's outskirts with several artillery rounds resulting in a dozen injured and some property damage, also Finnish commando units managed to infiltrate across the border under the dirge of the artillery and sabotaged infrastructure. Through out the later morning the Russian advance began, supported by armour and artillery the spearheads collided with well entrenched Finnish positions and heavy fighting ensued. In the South the 6th army led by Wrangel saw 6 independent armour divisions support the main infantry advance, however the artillery had turned the land into tough terrain that slowed the advance and almost halted the armour, by the 19th the first lines of the Finnish defence had been breached all along the front apart from those around Suoyarvi, the combination of heavy woodland, strong defence layout and veterans of the Finnish legion fresh from the European war held the Russians at bay.
Russian artillery looses itself upon the Finns
Over the coming days the sheer weight of Russian forces overcame Finnish defences in the north however the defensive positions in Eastern Karelia were holding strong and Russian losses were climbing with little to no gains to show for it, on the Karelian Isthmus the Finnish lines began to buckle. Russian tank doctrine was put to the test as light T-70's and T-26's exploited break through to rush into the enemies rear and isolate enemy strong points as heavy ''siege tanks'' the KV-1's and 2's lumbered up to these points and proving impervious to the Finnish 37mm anti tank guns, tore apart the strong points and bunkers as the infantry mopped up. By the 14th of April Viipuri had fallen after a small skirmish and with it the Karelian Isthmus was under Russian control as the Finnish forces retreated back into Finland proper, with the attack in Eastern Karelia running in serious difficulties a large portion of Army Group South moved to strike the Finns in the rear as the light armour divisions began the race along the undefended highway to Helsinki.
KV-1's advancing into Finland
By the 22th the Finnish army was in a state of collapse, their only combat worthy troops where in Eastern Karelia and by now encircled and Russian army divisions barrelling along the undefended Finnish coast towards Helsinki. Seeing the bleakness of further resistance the Finns sought terms with the Russians, they offered Finnish neutrality and the ceding of Karelia, however Moscow was not impressed. The Finnish refusal to hand over Karelia peacefully irritated Russia and it was decided that the Duchy of Finland would be restored and the question of Finnish independence given a resounding answer, the Finnish offer was rebuffed and informed that only complete surrender would do.
Complete capitulation will suffice
By the 27th Helsinki fell after a short but vicious battle centred around the government buildings, in the far north Oulu had fallen to Army group North and Russian troops moved to occupy the Swedish border, the Finnish forces in Eastern Kareli surrendered after a vicious mauling. All that remained was to take the city of Tampere and Finish organised resistance would end.
The Finnish parliament burns after the battle of Helsinki
Remaining Finnish resistance organised around Tempere in preparation for the oncoming Russian assault. A Russian amphibious operation secured the Aland islands to prevent any Swedish ideas of occupying them. For the remainder of April and all of June Russian forces mopped up isolated Finnish units and occupied most of the country and then surrounded the last bastion of the Finns in Tempere, on June 23rd the final attack began, battered, demoralised and under-supplied the Finns put up resistance till June 10th when the city finally fell. The remains of the Finnish state and military surrendered and Finland became the latest portion of the vast Russian empire. Russia would now not have to fear a hostile Finland, Saint Petersburg was now safe and Russia had met a German armed and trained nation in battle and proved the superior. 80,000 Russian causalities were sustained mainly in Eastern Karelia and the Isthmus to 60,000 Finn losses.
Tempere, and with it, Finland falls
The war was resounding a one sided affair, Finland couldn't hope to last against the Russian invasion for long. The war brought much combat experience needed in Russia for the advancement of doctrine and tactics needed to engage in modern warfare, the first Russian tank on tank combat happened during the war. German made Stug and Panzer III's had proved effective against Russian light tanks, however their 50mm and shortbarrel 7.5cm proved completely impotent against the armour of Russian heavier tanks and the slanted armour of the T-34, several examples of captured Finnish armour would be taken to the Yekaterinburg proving grounds for testing and evaluation. With the war won, Moscow had to win the peace in Finland, this was done by maintaining Finnish autonomy. While the Finnish Parliament was abolished, a Finnish Diet was instituted, the Finish army was integrated as an army corps within the wider Russian army, Finland would become a Kingdom within the Russian empire instead of a grand duchy and the elderly King Fredrik was permitted to keep his throne, however upon his death the crown would pass to the Russian Tsar. Finland became an autonomous Kingdom with in the Russian empire, and also the first democratic part of the Russian empire when regional elections to the Diet were carried out.
Now it remains to be seen if Russia could win the peace
The Russian Kingdom of Finland