How did Martin Luther change history?
The most important thing Martin Luther did to change history was to translate the Bible into words common people could understand. He did this in German, which lead the way for the King James English translation. He also challenged the all-powerful Roman Catholic Church and opened the door for Protestant reformation, a period of wars and further challenges to the political power of the Pope across Europe.
Credited for starting the Reformation. This had many affects on the world. The Catholic Church was no longer the only game in town, so to speak. He brought free thinking to the masses because he believed everyone should have access to the Word of God. Here a couple of good sources on this: History Channel had a great special on the Reformation and answered your question to the “T”. Also if your not afraid of a religious web site check out The Reformation Study Center on line. Should be able just to Google it.