Short answers, pulled from the story.
Holy Roman Emperor Henry IV walked barefoot through the snow for three days to beg forgiveness from Pope Gregory VII outside the gates of Canossa. This event marked the flashpoint of a fifty-year struggle that redefined the relationship between church and state in medieval Europe.
The Dictatus Papae document declared that the Roman church was founded by God alone and that the pope held the exclusive power to depose an emperor. It also stated that the pope alone could appoint or depose churchmen or move them from see to see.
The Investiture Controversy finally ended on the 23rd of September 1122 near the German city of Worms. Pope Callixtus II and Holy Roman Emperor Henry V entered into the agreement known as the Concordat of Worms.
The agreement eliminated lay investiture while allowing secular leaders some room for unofficial but significant influence in the appointment process. In Germany, the election of bishops and abbots was to take place in the emperor's presence as a judge, free of bribes.
The long war over investiture caused Germany to lose intellectual leadership in western Europe and fall behind advances in philosophy and law. The first German university, the Heidelberg University, was not established until 1386.