The Holocaust (capital 'H') and the "6 million" estimate relates to deaths of Jewish people only, by any means by the Axis powers, i.e. including starvation - not only by execution, and not only in gas chambers. Here is a post on the 6 million; it includes links to a few more posts on numbers

• How many Jewish people were actually killed during the Holocaust?

And, if terminology and overall counts are of interest, check out these posts

• When was the first time that the Holocaust was referred to as the Holocaust?

• Holocaust Historiography: the question of non-Jewish victims of Nazi extermination

• Holocaust numbers 15-20 million

• Why is the Holocaust associated more with Jews than the other victims?

• Jewish vs. non-Jewish experience in WWII camps + why the Poles/Slavs aren't discussed as much?

• My old dictionary has only one listing for holocaust, as a common noun, lower-case "h". New dictionaries also list Holocaust, proper noun, upper case "H". What's the story behind this change?

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