Mainly the ones under the Nazi yoke, but also many in the territories of the the Nazis' allies.
The biggest losses were in Poland, the countries of the former Soviet Union, especially Lithuania, Latvia, Belarus, Ukraine - also Germany, Austria, the Czech Republic, Romania ... the Netherlands, France.
Every Jewish community in Europe was affected.
The British Jewish community, while not affected directly by the Holocaust, as Hitler did not control the United Kingdom, was put under much duress by the attempt emigrations of European Jews and by the Battle of Britain and other national British calamities.
European ones.
Most of those in occupied Europe.
The US Army suffered the greatest losses on D-Day, particularly at Omaha Beach.
Gallipoli
Russia.
Russia suffered the greatest loss of life during World War I. There were thousands of casualties on all sides suffered during the war.
those in the 'Pale of Settlement' and Poland suffered the worst.
Most of those in occupied Europe.
None for thier political beliefs. People only died in the Holocaust for being Jewish. The Nazis were responsible for killing political opponents even before they were elected (as they also suffered losses), the actions against political opponents pre-date the Holocaust and most of the actions completed by then.
Russia suffered the biggest losses during WW1.
The US Army suffered the greatest losses on D-Day, particularly at Omaha Beach.
Russia
Gallipoli
The Nazis rounded up Jews and sent them to special camps where they were killed. The European Jewish population in 1950 was 3.5 million people in contrast to the 1933 European Jewish population of 9.5 million people (a difference of 6 million people whence the 6 million number comes). 2 million of the 3.5 million remaining Jews were in the Soviet Union.
Germany
Yes, losses is the plural form of loss, e.g.:The company's losses were huge.Manchester United suffered several losses at the start of the season.
YES/True
The phrase is simply used to show that just as the American's suffered devastating losses in Vietnam, the Soviet Union had crushing losses in Afghanistan.