English and German are both Germanic languages. They have the same root origins.
Yes, Russian is a Slavic language. Slavic languages share common roots and belong to the same language family, which includes languages such as Polish, Czech, and Ukrainian.
Primarily Yes. High German (which is the German spoken in Germany) is the official language of Austria. Nearly all Austrians can speak High German, but a minority in the more rural, mountainous areas speak local dialects of German that are quite different from High German. Some Germans find these dialects of German difficult or impossible to understand.
It means that you speak in the same language
The same language I speak in any location.
You speak the same language you spoke at the beginning of World War I.
For the same reason you speak English. That's their language. (However English is not your native language, I think)
Each person would speak the same language. Same can be said about any language.
Not necessarily. A language family can have dozens of different languages in it.
There are numerous religious groups that may speak the same language, as language and religion are not necessarily correlated. The number of different religious groups speaking the same language will vary depending on the specific language and region in question.
it's the same way as any other language. How people speak English or Spanish or any other language..?
they do not speak the same because they are different tribes