For a couple of months, the horribly outnumbered Finnish troops had held their Soviet counterparts at bay. Their only real allies in this fight against a vastly superior force had been Red Army arrogance, solid tactics, a brutally cold winter, and sisu (a word coined at this time that, roughly translated, means “guts”). But they used all of them to the fullest and gained the admiration of much of the world…though with that admiration came precious little help.
Then General Timoshenko arrived and got things on the Soviet side a bit more organized, and the Finnish situation went downhill pretty quickly. A massive bombardment, begun on February 1, 1940 was followed by the final breakthrough. Keep in mind that Finland only had 150,000 men in its entire army, and those still able to fight had been employed without respite since hostilities started in November…they were completely exhausted and running low on ammunition.
So it comes as little surprise that the Red Army, ten days later, achieved the breakthrough from which the Finns could not recover. The Red Army was still suffering huge casualty counts, but outnumbering the Finns by better than 4-to-1 gaves the Soviets some “wiggle room”.
Throughout the Winter War, Finnish diplomats (even when they were sort of winning) tried to discuss peace initiatives with Moscow, but their calls were never answered. Joseph Stalin wanted a victory, and to accept peace terms in an already terribly embarrassing endeavor was beyond contemplation. But now, with victory seemingly on the horizon (and far more favorable terms able to be negotiated), a still-red-faced Soviet dictator was probably more willing to talk.
And so the peace delegation from Finland landed in Moscow and began negotiations on March 8, 1940. They would be concluded four days later and the guns would fall silent one day after that.