One of the Night Wolves’ activities is the Moscow-Berlin Victory Ride, which the group first attempted last year, in honor of the 70th anniversary of the end of what Russia calls the Great Patriotic War and the rest of the world remembers as World War II. (Then, too, they had to bypass Poland.)

That the most direct route from Moscow to Berlin runs through Poland is not merely a matter of geography. In 1939, Hitler and Stalin divided the country between them in a secret protocol to the Hitler-Stalin pact. After taking possession of its share, the Soviet Union executed, arrested and deported hundreds of thousands of Polish citizens. Soviet terror reigned in eastern Poland for nearly two years before Hitler attacked the Soviet Union. According to Soviet and now Russian historiography, this was when the war began — and this is the main distinction between World War II and the Great Patriotic War.

When it was over, the Soviet Union kept a chunk of eastern Poland, and with the acquiescence of the Western powers, exercised dominance over Eastern Europe and made the Polish capital the nominal center of the Warsaw Pact, the Soviet bloc’s answer to NATO.

After the Eastern bloc and the Soviet Union collapsed, Russia gingerly broached the subject of the violence it had inflicted on Poland, but stopped well short of a proper reckoning. Possibly the biggest, and certainly the most heavily symbolic, part of history that Russia has never fully acknowledged is the massacre in 1940 of several thousand Polish officers and intellectual leaders in what has become known as the Katyn Forest, outside the city of Smolensk, in central Russia.

For decades, the Soviet Union blamed German troops, who occupied the area starting in 1941, for the Katyn massacre In the 1990s, Russia began releasing information about the executions. It was a painful, two-steps-forward-one-step-back process, and Russia has never fully acknowledged Soviet culpability.