In the aftermath of the Great War localized conflicts engulfed Eastern Europe between 1917 and 1919. Many attacks were launched against Jews during the Russian Civil War, the Polish-Ukrainian War, and the Polish–Soviet War ending with the Treaty of Riga. Almost half of the Jewish men perceived to have supported the Bolshevik Russia in these incidents were in their 20s. Just after the end of World War I, the West became alarmed by reports about alleged massive pogroms in Poland against Jews. Pressure for government action reached the point where U.S. President Woodrow Wilson sent an official commission to investigate the matter. The commission, led by Henry Morgenthau, Sr., concluded in its Morgenthau Report that allegations of pogroms were exaggerated. It identified eight incidents in the years 1918–1919 out of 37 mostly empty claims for damages, and estimated the number of victims at 280. Four of these were attributed to the actions of deserters and undisciplined individual soldiers; none was blamed on official government policy. Among the incidents, during the battle for Pińsk a commander of Polish infantry regiment accused a group of Jewish men of plotting against the Poles and ordered the execution of thirty-five Jewish men and youth. The Morgenthau Report found the charge to be "devoid of foundation" even though their meeting was illegal to the extent of being treasonable. In the Lwów (Lviv) pogrom, which occurred in 1918 during the Polish–Ukrainian War of independence a day after the Poles captured Lviv from the Sich Riflemen – the report concluded – 64 Jews had been killed (other accounts put the number at 72).