It’s Time to Bring Back the Polish-Lithuanian Union

In 1386, the last pagan ruler of Lithuania, Jogaila, married the child queen of Poland, Jadwiga, then in her early teens. The marriage created a political union between Poland and the Grand Duchy of Lithuania, which encompassed large parts of today’s Belarus and Ukraine. By doing so, it solved a twofold problem. One, it helped bring the vast Eastern European territories, including lands of the former Kyivan Rus’, into the fold of Western Christendom. Two, the union addressed the immediate security concern facing both Poles and Lithuanians: the threat of Teutonic Knights.

The Polish-Lithuanian Commonwealth would go on to become one of the largest countries in Europe and a fascinating laboratory of political governance, studied in some detail by the United States’ founding fathers, particularly in the Federalist Papers. After the end of the Jagiellonian dynasty, it transformed into an electoral monarchy, similar to the city-states of Italy yet operating on a vastly larger scale. The commonwealth’s legislature and local diets followed the principle of unanimity—not unlike the European Council does on many issues today. The commonwealth’s atmosphere of religious tolerance and freedom enjoyed by its nobility provided a stark counterpoint to the absolutist monarchies of Western Europe—not to speak of the tragic history that followed the commonwealth’s demise in 1795.

What if a similar political solution were available to the problems facing Ukraine and Poland today?

The argument for an explicit political union between the two countries is not based on nostalgia but on shared interests. To be sure, due to four centuries of common history within the Polish-Lithuanian Commonwealth, much of today’s Ukraine (and Belarus) shares far more of its past with Poland than it does with Russia, notwithstanding claims of Russian propagandists to the contrary and notwithstanding the fact that the relationship was oftentimes highly complicated, as illustrated by events of the 17th-century Deluge—most prominently by the Khmelnytsky uprising and its conflicting interpretations by Poles and Ukrainians.

Fast-forward to the present and to the near future, however. Both countries are facing a threat from Russia. Today, Poland is a member in good standing of the EU and NATO, while Ukraine is keen to join both organizations—not unlike the Grand Duchy of yesteryear, eager to become part of mainstream, Christianized Europe. Even if Ukraine’s war against Russia ends with a decisive Ukrainian victory, driving degraded Russian forces out of the country, Kyiv faces a potentially decades long struggle to join the EU, not to speak of obtaining credible security guarantees from the United States. The poorly governed, unstable countries of the Western Balkans, prone to Russian and Chinese interference, provide a warning about where prolonged “candidate status” and European indecision might lead. A militarized Ukrainian nation, embittered at the EU because of its inaction, and perhaps aggrieved by an unsatisfactory conclusion of the war with Russia, could easily become a liability for the West.

Imagine instead that, at the end of the war, Poland and Ukraine form a common federal or confederal state, merging their foreign and defense policies and bringing Ukraine into the EU and NATO almost instantly. The Polish-Ukrainian Union would become the second-largest country in the EU and arguably its largest military power, providing more than an adequate counterweight to the Franco-German tandem—something that the EU is sorely missing after Brexit.

For the United States and Western Europe, the union would be a permanent way of securing Europe’s eastern flank from Russian aggression. Instead of a rambling, somewhat chaotic country of 43 million lingering in no-man’s land, Western Europe would be buffered from Russia by a formidable country with a very clear understanding of the Russian threat. “Without an independent Ukraine, there cannot be an independent Poland,” Poland’s interwar leader, Jozef Pilsudski, famously claimed, advocating a Polish-led Eastern European federation including Lithuania, Belarus, and Ukraine—basically a recreation of the medieval commonwealth.

This is not fantasy talk. Early on during the war, Poland passed legislation allowing Ukrainian refugees to obtain Polish ID numbers, giving them thus access to a host of social and healthcare benefits normally reserved for Polish nationals. The Ukrainian government vowed to reciprocate, extending to Poles in Ukraine a special legal status not available to other foreigners. With over 3 million Ukrainians living in Poland – including a sizeable pre-war population – the cultural, social, and personal ties between the two nations are growing stronger every day.

There is also one obvious precedent for a political union that significantly upended the balance of power in the EU and jumped through many of the obstacles that a prospective Polish-Ukrainian Union would face: German reunification. Following the first free election in East Germany in March 1990, the new Christian Democratic government quickly negotiated a treaty establishing a monetary, economic, and social union between East and West Germany, effective July 1 of that year. Not only did the Deutsche mark become legal tender in East Germany, but East Germany also adopted West German legislation governing economic activity—from antitrust, labor, and environmental regulation to consumer protection—and proceeded to dismantle any lingering remnants of communist rule.

This was only the first step toward political unification. It was followed by East Germany acceding to Germany’s constitution, the Basic Law—much like the Saarland did when it joined West Germany in 1956. A complex unification treaty governed in minute detail which parts of former East German law would remain in effect and which ones would be superseded by West German law, how, and under what timelines. Simultaneously, an agreement between Chancellor Helmut Kohl and Soviet leader Mikhail Gorbachev in the summer of 1990 cleared the path toward NATO and European Economic Community (EEC) membership for a unified Germany. In the EEC, German unification prompted a treaty revision, leading ultimately to Germany’s abandonment of its beloved Deutsche mark in favor of the euro.

There is no downplaying the complexity of the unification, particularly of its legal and regulatory aspects, which were complicated further by Germany’s European commitments. Yet the German example demonstrates that such an exercise is possible when sufficient political will exists. Less than 11 months from the fall of the Berlin Wall, East Germans became full-fledged citizens of the Federal Republic on Oct. 3, 1990.

There are some obvious differences between the Polish-Ukrainian situation of today and the German one of the early 1990s. For one, notwithstanding the shared culture, history, and linguistic connections—and the presence of a large Ukrainian population in Poland—the idea of “absorbing” Ukraine into Poland is an obvious nonstarter. Unlike in 1990, when East Germans contended themselves with embracing the existing West German Basic Law and, in fact, the entire legal and political system of their more developed democratic cousins, a Polish-Ukrainian union would require drafting a new constitutional document and building shared federal or confederal institutions—in addition to what would be a complex unification treaty.

Subsidiarity ought to be the guiding principle of such efforts, particularly because the purpose of the union would not be to efface Ukrainian identity or statehood—quite the contrary. Areas where Polish law should make it into the Ukrainian legal system, at the earliest opportunity, are those that are necessary for Ukraine’s effective functioning within the EU and its single market. There are other areas, however, where such harmonization is not necessary—either because they lie completely outside of the EU’s competencies or because Ukrainians could find ways to comply with EU law on their own terms within predefined timelines.

Arguably, the biggest challenge of German reunification involved the economic gap between the two constituent parts. Since 1990, more than $2 trillion is estimated to have been transferred from the West to the East, or around half of Germany’s annual GDP, much in the form of transfers through the welfare system. In real terms, East German incomes were roughly one third of those in the West—a similar difference to the one between Ukraine and Poland before the war. The main difference, of course, is the relative size of the two countries—whereas the population of East Germany was just a quarter of that of West Germany, Ukraine’s is larger than Poland’s.

It is not reasonable to expect the Polish welfare system to become a major vehicle of redistribution to the east; in fact, Polish taxpayers should not be paying the bill for Ukraine’s reconstruction and its catch-up growth at all. Besides Russian assets—particularly the $300 billion held by its central bank currently frozen in Western financial capitals—the EU and its affluent Western European member states will have to step up. But that is not news, regardless of the nature of the postwar political settlement. What is new about the idea of a Polish-Ukrainian Union is that its emergence would create a political and legal environment in which the money spent would not be directed at a country lingering in the EU’s waiting room but at a member state, with all the rigor and scrutiny that comes with it.

There are many potential objections. The central one is the idea’s realism. Why would Poles take on a radical enterprise of such proportions? And why would Western European nations acquiesce to (and largely pay for) the rise of a new European power that irrevocably shifts the EU’s center of gravity to the east?

The answer to the first question is simple: Russia’s aggression and its failure opens new opportunities for statecraft. Political leadership is about responding creatively to the challenges of one’s time, not about trying to apply an old toolbox (in this case, a 1990s-style approach to EU and NATO enlargements) to a new situation. A Polish-Ukrainian Union may well be the most straightforward way through which postwar Ukraine is turned into a stable, prosperous, and strong country that will be able to keep Russia at bay—something that is keenly in Warsaw’s interest.

As for the second question, note that Brussels, Berlin, and Paris have already made a commitment to enlarge the EU by granting Ukraine candidate status, with everything that it would entail. An explicit political union between Poland and Ukraine would make it impossible to stall and weasel out of that pledge, as one may expect they eventually will. Opposing such a union, furthermore, would mean opposing one of the basic attributes of Ukraine’s national self-determination, which European leaders have vowed time and again to protect.

That is where U.S. leadership comes into play. Given the investment already made into Ukraine’s success on the battlefield, which far exceeds Western European contributions, Americans have a keen interest in turning Ukraine into a success story, particularly as the war itself moves into the rearview mirror. Given old Europe’s chronic fecklessness, illustrated by the EU’s misadventures in the Balkans, Ukraine’s future is too important to be left in the hands of Brussels, Paris, and Berlin. If Warsaw and Kyiv were willing to step up and solve the Eastern European problem once and for all, the U.S. administration must have Poland’s and Ukraine’s backs.