Upon their arrival in Germany, the Nazi government sent most of non-ethnic Germans to concentration camps. Only some of them were freed after the protests of the Romanian government. During World War II, when the region returned under the control of the Romanian administration, the Jewish community of the area was largely destroyed by the deportations to ghettos and Nazi concentration camps, where about 60% died. Despite the anti-Semitic policies of the Ion Antonescu's government of Romania, the mayor of Cernăuți, Traian Popovici, now honored by Israel's Yad Vashem memorial as one of the Righteous Among the Nations, saved ca. 20,000 Jews. In 1944, when the Soviet troops returned to Bukovina, many inhabitants fled to Romania, and Soviet persecutions resumed, with the result that the region was seriously depopulated. In demographic terms, these war-time and post-war-time factors changed the region's ethnic composition. Today the number of Jews, Germans and Poles is negligible, while the number of Romanians has decreased substantially. Ruthenian communities in Bukovina date back to at least 16th century. In 1775, Ukrainians (Ruthenians) represented some 8,000 out of a 75,000 population of Bukovina. By 1918, as a result of immigration of Ukrainian peasants from nearby villages in Galicia and Podolia, there were over 200,000 Ukrainians, out of a total of 730,000. Most of Ukrainians settled in the northern parts of Bukovina. Their number was especially large in the area between the Dniester and Prut rivers, where they became a majority. A similar process occurred in northern Bessarabia. Throughout the history of the region, there were no inter-ethnic clashes, while the city of Chernivtsi was known for its German-style architecture, for a highly cultivated society, and for ethnic tolerance. Small ethnic disputes were, however, present on occasion. In 1918, many Ukrainians in Bukovina wanted to join an independent Ukrainian state. After an initial period of free education in Ukrainian language, in late 1920s Romanian authorities attempted to switch all education to the Romanian language. In 1940-1941, the Soviet reprisals were more massive in the parts of the Chernivsti oblast were Romanians predominated; when, however, after 1944, Ukrainian anti-Soviet resistance rose up, Romanians and Ukrainians fought alongside against NKVD.