What does Warren mainly talk about?

The story mainly tells that Zosia, a Polish girl living in Volhynia, fell in love with a Ukrainian boy, but her parents decided to let her marry a Polish widower. Soon, World War II broke out and the situation was tense. Zosia, in the war, had to try to survive. ......

The story begins with a happy wedding in a village in Vornia, Eastern Europe in 1939. The eldest daughter of a Polish family married a Ukrainian. The youngest daughter Zosia also has her own Ukrainian sweetheart, but her father married her to a rich old Polish widower for money and land.

In troubled times, the wind and water turn, and the Soviet Red Army will escort all Poles into exile. Ukrainian boys lied to the officers that they had excellent vodka as a bribe to save Zosia. Later, the policeman who stole the wine came to the Ukrainian boy's house and shot him in the head. Then the Germans occupied vornia and the rich were released. This time, the Jews will be wiped out. Jews hide in Tibet and cannot escape bad luck. Then the infamous Ukrainian UPA was established and Ukrainian nationalism rose. As a result, due to the propaganda of war, politics and nationalism, the areas where ethnic groups once merged began to slaughter another ethnic group indiscriminately.