Thucydides, that sounds fair enough. I am not actually for the disbanding of religion because believe it provides a strong social glue and there is far too much cultural inertia at this junction to expect such a drastic change. Despite that I don't believe that our morals come from religion, I do recognize that in the hands of the right people, religion makes bad people do good things, though I do have qualms about within who's hands that power lies. At the risk of being called a rabid science proselytizer I would like to point out that while science and religion will surely always have unanswered question, the point remains that science has already answered a great deal more questions than has religion, with the evidence to back it up, and is continuing to offer many answers concerning the wondrous phenomena of our physical world. I think that when you weigh the two, you'll find that the scientific method carries much more credible weight.
"Absolute rubbish. A Gothic army was responsible for the Middle Ages, Europe was becoming more and more Catholic as the years went on(and that has nothing to do with the Goths) so Europe would have been Catholic anyway, Middle Ages or not. Nothing that went wrong in the Middle Ages can be blamed on Catholicism. Yeah I know what's coming next so I'll get it out of the way: although the Crusades were a religious undertaking the Crusaders were actually more interested in adventure and money just pretending that religion was why they were going to Jerusalem and the Crusaders brought back many helpful things: oranges, the Arab numerical system(1 instead of I, 4 instead of IV et cetera) and washing oneself regularly for example."
You can't say that the Middle Ages were caused by the sacking of Rome any more than one can say they were "caused" by the Catholic Church. The Middle Ages is simply the name of the period that doesn't necessarily mark a distinct period that has some sort of root cause. But in the period commonly known as the Middle Ages in Europe, the Catholic Church was the main unifying influence and was definitely one of the most important influences on the culture and social structure of the time, along with urbanization and feudalism.
You can't say Europe was becoming more and more Catholic and would have ultimately ended up Catholic... I don't even know what you mean by that. It seems that you've completely ignored the Schism and the Protestant Reformation, which clearly mark the slow decline of the Catholic Church, not to mention the rifts in the papacy.
These were caused by the corruption in the Catholic Church, such as the sale of indulgences as well as the justification of murder of infidels. The Crusades absolutely were motivated by money, but it was money for the Catholic Church. Religion was wielded as justification for the Crusades as well as most action taken at the time, any war, any change in legislation, it all had to be laid side by side with the views of the Catholic Church. This is why they became immensely powerful, and became major land owners. They wielded absolute power as they could interpret scripture in any manner that benefited them. It was this that motivated many to think critically and question the Catholic Church and form the Protestant movement whereby the bible could be interpreted more personally, rather than by a corrupt pope. The Crusades may have been a major cause of the resulting Renaissance through the diffusion of classical knowledge kept and improved upon by Islamic scholars, but the ends don't exactly justify the means. I would say that the Middle Ages was more ended by the Islamic victories, the monopolization of the silk road by the Ottoman Empire forcing the search westwards for new passage to the Orient, the decreasing faith in the Catholic Church and increasing humanism, and the Black Plague which freed most serfs from the bounds of feudalism and greatly contributed to religious doubt.
In the end, almost everything that happened in the Middle Ages of Western Europe, both good and bad could be credited/blamed upon the Catholic Church. It's just that through today's cultural lens, we tend to view the Middle Ages as more bad than good, though I don't necessarily agree.