It’s not a secret that Ukraine’s aspirations to have closer economic and political ties with the West — and with the European Union in particular — are at the center of its current face-off with Russia. But developing those ties is much easier said than done. In its present state, no one would mistake Ukraine for a European country. Its economy and its political institutions have hardly progressed since 1991, the year the country broke away from the Soviet Union.

Ukraine is fortunate that Poland — a neighbor that successfully managed a similar transition after winning independence from Moscow after the communist period — has shown extraordinary interest in Ukraine’s integration into Europe. Ukraine’s European future will largely depend on the special relationship that has quietly developed between Kiev and Warsaw. 

The friendship should not be taken for granted. Poland and Ukraine have a long history, very little of which is cordial. In 981, Vladimir the Great, grand prince of Kiev, expanded his empire by sacking a number of Polish cities. For centuries afterward, the populations of both countries fought viciously over territory, using forcible population transfers and heavy-handed cultural imperialism to cement their regional influence. The sixteenth and seventeenth centuries were especially violent. It is estimated that 100,000 Poles and 20,000 Ukrainians were killed in ethnic purges during this time. 

The modern history of Polish-Ukrainian relations isn’t much rosier. Between 1942 and 1944, some 60,000 Poles were murdered in purges carried out by Ukrainian nationalists in Volyn, a region to which both countries had historic ties, but which had recently been absorbed by Ukraine. (Ukrainians were concerned that Poland was intent on reclaiming the territory for itself.) In 2009, the Polish parliament passed a resolution calling those purges a “mass murder that has the character of ethnic cleansing.”