In the summer of 1920, Russia seemed poised to take over Europe.

Newly victorious in the Russian Civil War, but convinced that the capitalists were bent on strangling the cradle of Communism, the Bolsheviks looked for salvation. Their gaze fell on Germany, exhausted and embittered by defeat in the First World War, and now engulfed in civil strife between Communist revolutionaries and protofascist freikorps paramilitaries. If only the Red Army's bayonets could install a Bolshevik regime in Berlin, then the two most powerful states in Central and Eastern Europe would be united in a Communist monolith. And from there, perhaps Communism would spread to Italy, France, Hungary and beyond. Could Marx's prediction of world revolution finally be at hand?

Unfortunately for Lenin and Trotsky, an obstacle stood in their way. It was called Poland.

Like Communist Russia, Poland was also a new nation, though of a very different kind. The Bolsheviks only needed to overthrow the Tsarist government to take over the Russian state: the Poles had to create their own state. Though the seventeenth-century Polish-Lithuanian Commonwealth had extended deep into present-day Russia and Ukraine, Poland as an independent nation had been snuffed out in the eighteenth century, its territory partitioned between the Russian, German and Austrian empires. When those empires collapsed after World War I, the Poles took advantage of the chaos to resurrect their nation.

Yet as they had for centuries, Poland and Russia again would go to war. One reason was rival claims for the borderlands between the two nations—those "bloodlands" of Belarus and Ukraine that were perpetual battlefields. The deeper cause was geography; a glance at the map shows that the land bridge from Moscow to Berlin runs through Poland, whose unfortunate fate was to be wedged between Germany and Russia.

The Bolsheviks saw Poland as a semifeudal state of nobles and rich landowners exploiting the workers and peasants. The Poles feared the Red Army would march through Poland on the way to Germany, and never leave. Ironically, the Poles had refused British entreaties to help the Whites defeat the Reds for fear that the former Tsar's generals would be just as likely to reclaim Poland for the Russian empire.

War would pit David-ski versus Goliath-ovitch. Britain and France rated Poland's chances for victory as nil against a Russian colossus endowed with vastly superior manpower and resources. But the West had not reckoned on the force of Polish nationalism and the powerful personality of Field Marshal Josef Pilsudski, the self-taught general who proved far shrewder than the professional military officers who had so badly bungled Verdun and the Somme.

Peace talks continued while both sides prepared for war. Poland struck first, launching a preemptive offensive in April 1919 that swiftly seized Kiev. But they failed in their goal to destroy the retreating Russian armies and, even worse, discovered that the Ukrainians hated Polish occupation as much as they did the Bolsheviks. Poland also learned that nationalism cuts both ways; thousands of patriotic Tsarist officers, a group once targeted for murder by the Communists, now offered their professional expertise to the Red Army in patriotic outrage against the Polish attack.

The tide turned against Poland. Led by Marshal Mikhail Tukhachevsky, the genius of mechanized warfare later executed by Stalin, the heavily reinforced Russian armies marched on Warsaw, driving the outnumbered and outgunned Polish forces before them.

The fighting was epic, colorful and merciless. The Poles raised divisions of enthusiastic but inexperienced and poorly armed volunteers, leavened by their countrymen who had learned soldiering in the armies of Germany, Austria and Russia. From America came the Kosciuszko Squadron of American volunteer pilots. From France came the Blue Army, a Polish force trained and equipped by the the Allies to fight on the Western Front, and which even brought its own tanks.

But the Bolsheviks had their 1st Cavalry Army, the dreaded Konarmiya, a horde of thousands of fast, hard-hitting horsemen led by mustachioed Marshal Semyon Budyonny. Russia also had sympathizers abroad; British dockworkers and German and Czech railwaymen heeded Moscow's call to save the socialist motherland and refuse to load supplies for Poland. Just as in 1939, Britain and France promised support but did little, other than to send a few advisers (Charles de Gaulle among them) who claimed much credit but contributed very little to the Polish war effort.

The Russo-Polish War was a world apart from the trenches and barbed wire of the Western Front. As Hitler's armies later discovered, the East was simply too vast for armies to form continuous lines of troops, which made warfare far more mobile. The plains of Central Poland lacked defensible terrain, and neither side had the time or resources to build the trenches that stalemated the Western battlefields. In France, cavalry had become an anachronism that sat idle while the infantry and artillery did the fighting. In Poland and Ukraine, the mobility and shock power of cavalry ruled. Despite the handful of tanks and airplanes, the fighting was almost Napoleonic, as Cossack horsemen and Polish lancers clashed in the last major cavalry battles in history.

There was no thought of mercy. Russians butchered Polish soldiers, though officers were first tortured before being killed. The Poles behaved likewise. As always, the Jews were victims: Polish and Russian troops both continued their traditions of looting and murdering them at will.

By August 1920, Warsaw appeared doomed as the Red Army advanced on the city, where Communist sympathizers were already rising. But the Russian offensive was disjointed; the more that Tukhachevsky and his armies in central Poland drove on Warsaw, the more jealous became Stalin, who helped command the Russian forces in southern Poland. Instead of supporting Tukhachevsky, Stalin aimed to drive south to liberate the workers and peasants of Hungary, Austria and Italy.

Just as all seemed lost, Marshal Pilsudski unleashed his masterstroke, a move worthy of Robert E. Lee or Rommel. While the central Russian armies were fixated on Warsaw, a Polish strike force sideslipped to the south of the city, and then turned north in a left hook into the exposed Russian flank. Surprised, demoralized and outmaneuvered, the Russian armies disintegrated, with some retreating back to Russia and others fleeing to German territory to be interned. Pilsudski's counteroffensive was assisted by the breaking of Russian codes, a Polish specialty that they later used to crack the Nazi Enigma machine.

The Poles called it the "Miracle on the Vistula." Not only had the new Polish nation survived, but the ensuing peace agreement gave it much of the disputed territory. The cost for both sides totaled more than one hundred thousand dead and further devastation of war-wracked economies.

Poland had defeated Russia, but this quite a case of good defeating evil. Poland between World War I and II was ruled by authoritarian governments that imposed or tolerated anti-Semitic measures that Hitler's brownshirts would have approved of. In 1938, Poland even joined Hitler in dismembering Czechoslovakia as it grabbed its share of Czech territory.

Nonetheless, in 1920, Poland had stopped the Communist Revolution in its tracks. Had Poland fallen before the Red Army and advanced into a tired, war-ravaged and disillusioned Europe, then much of the continent—Germany, Hungary, Italy—might have gone Communist. Some naive souls might have looked forward to the workers and peasants breaking their capitalist chains. The reality would probably have been Stalin's NKVD secret police conducting show trials in Berlin and Paris.

In the event, Poland's independence was again tragically cut short by the Nazis in 1939, after which the country was "liberated" by the Soviets for a forty-year occupation.

Then the Soviet empire also crumbled. Poland became free, only to recently elect an authoritarian government. On its border is a nationalistic Russia that has attacked Ukraine and is now asserting its influence in Eastern Europe.

For the sake of Poland and Russia, let's hope history doesn't repeat itself.

Michael Peck is a contributing writer for the National Interest. He can be found on Twitter and Facebook.

For further reading:

"Warsaw 1920: Lenin's Failed Conquest of Europe" http://www.amazon.com/Warsaw-1920-Lenins-Failed-Conquest-ebook/dp/B002SDRTKQ/ref=sr_1_3?s=books&ie=UTF8&qid=1459535585&sr=1-3&keywords=battle+of+warsaw

"White Eagle, Red Star" http://www.amazon.com/White-Eagle-Red-Star-Polish-Soviet/dp/0712606947