Question

Why was it important that Luther translated the Bible into German?

Answer 1

Aside from the obvious that it allowed Germans to read the Bible without learning Latin, it's important because he largely invented the modern German written language in the process. Once the Bible was available in German the people had an incentive to learn how to read. Not only did he provide the Germans with a way to read the Bible in their own language, he also provided the impetus for widespread German literacy and literature.

It should also be noted that in translating the Bible into German Luther discarded the standard Roman Catholic canon of Old Testament books and only included those books that are in the standard Hebrew bible. This set the stage for the Authorised Version of the Bible in English (aka King James Bible) which does not include the books now known as "The Apocrypha". His translation also encouraged others to translate the Bible into their own languages, including the English.