The Investiture controversy was a time when the Holy Roman Catholic Church and the Roman Empire had differences in the way of territory and authority. The involvement between both sides were intermixed, the Laymen of the Western Roman Empire were involved in the Investiture Ceremony for the Bishops and Archbishops and vice-versa. These distentions of Investiture lead to many problems such as the Investiture controversy.(source) (source Google Books) (source)

An Investiture is a formal appointment of a person in to a special rank or role. This is often put into a ceremony, to mark this inauguration. This insignia was very important during the Middle Ages it was the one thing that inducted a person into a position. However this appointment of positions were challenged by the Roman Empire, the secular leaders and Religious ones were not clarified on the job positions and more often then not their job descriptions would cross over into each others. This involvement of each of the Imperial powers started with Charlemagne and the Pope crowning him Emperor, up until the 11th and 12th centuries this was not a problem. However when in came out the effects of it were great, it was the most significant conflict between the church and state in Medieval History. It had great impact on the Western Roman Empire. This alone led to over 50 years of civil war in Germany, not to mention other struggles in France. (source) (source) (source) (source Google Books)

The Popes acted in an offensive manner, challenging the European monarchy and as a result setting in place Bishops and Abbots to be in control. This challenging on the Popes side was the fight to establish political legitimacy. The popes of the Holy Roman thought that the European Monarchy was wrong because no man should have that authority that belongs to God. (source) (source Google Books) (source)

This fighting led to a compromise known as the Concordat of worms it stated that the secular leaders would have a place in the appointing ceremony. It also concluded that the monarchy power was broken and the localized lords would take charge. The Papacy gained much control for these efforts and then set the stage for the Crusades in the 12th century, which some say is why the efforts of this controversy ended. Some think it is because they needed to come together again and fight against the Muslims. Both are legitimate endings to these efforts. (source Google Books) (source)

The results of this time are huge; the impact on Germany alone took till the 19th century to recover. This fight was very effective on the Holy Roman Catholic Church side and established more power for the Pope. With out this power the Crusades may not have had the out come it did and the Crusades might have been a failure which would render many different consequences then we have today. This Controversy also had a great effect on the formation of the Protestant church. Throughout history there are so many interlinked effects and causes that all have an effect on each situation. (source Google Books) (source) (source)