Poland has taken back its highest national award from Ukrainian President Volodymyr Zelensky. The reason: Ukraine named a new military unit after a World War II armed group that killed tens of thousands of Polish civilians.

The group is called the UPA, a Ukrainian organization from the 1940s. Between 1943 and 1945, the UPA killed roughly 100,000 Poles in areas called Volhynia and Eastern Galicia. In Poland, these killings are still taught in schools and remembered every year. Almost every Polish politician considers it a major historical wrong that must never be forgotten.

When Ukraine announced it was naming an active military unit after the UPA, Poland saw that as deliberately disrespectful. Polish President Karol Nawrocki said in May that Poland should revoke Zelensky's award. The country then did so. The award is called the Order of the White Eagle. It was first created in 1705. When a foreign leader receives it, it means Poland sees them as a crucial ally. Taking it away sends the opposite message — a formal state act, not a casual remark.

This causes real problems. Poland has been one of Ukraine's biggest supporters during the war against Russia. Poland hosts more Ukrainian refugees than any other European country. Polish territory is the main route for weapons from the West into Ukraine. Poland also pushes hard in Europe for Ukraine to join NATO and the EU. A public fight between Poland and Ukraine helps Russia's propaganda and weakens the European coalition that Ukraine depends on.

For Polish President Nawrocki, though, the choice was politically necessary. No Polish leader can ignore an insult to the memory of the Volhynia killings without facing backlash at home. Naming a military unit after the UPA gave him a reason to act that his voters would support.

Ukraine sees the situation differently. In the western part of Ukraine, many people remember the UPA as a group that fought against Soviet control. Since Russia invaded in 2022, Ukraine has been rebuilding its national identity and celebrating figures and groups that resisted outside control. If Ukraine renames the unit under pressure from Poland, it would look to Ukrainians like the country is letting another nation control its own history.

This is the core problem: Poland and Ukraine each have a true version of history, but they point in opposite directions. Historians in Ukraine do not deny what the UPA did to Poles. They say that the UPA also fought against Nazi Germany and the Soviet Union, and that should count for something. Poland wants Ukraine to say: "The UPA was wrong to kill your people." But Ukraine's government cannot say that without its own people seeing it as weakness.

Nobody knows if this award revocation ends the argument or starts a longer period of tension. Poland and Ukraine have fought over other issues before — grain shipments, border rules, money — but stayed allied. This feels different because it is about national pride and memory, not trade or logistics. Stripping a wartime leader of a top honor while his country is fighting for its life sets a pattern that other European nations watching will remember.

The real damage will show up in how Poland and Ukraine work together on military supplies, shared intelligence, and EU support. Right now, they say they still have normal relations. But neither country wants a full break. What happens next — who gives ground, and how quickly — will tell us whether the European unity that formed in 2022 can survive clashes over history.