How about leaving out personal opinion of what may or may not have happened and what did happen? It is history, documented history.
The Irish spread Christianity back into the continent, advised rulers, copied text and passed on knowledge. We, as western civilization, would not be where we are without the influence of the Irish in our past.
The input of women into the article and the mention of the aforementioned book make this article worth little more than a book review. And civilization implies to a society organized with structure and law, not a "large and coordinated group of people." Hell, that could be a parade.
Also, we would not have what we have without the Irish. We would be centuries behind were we are. Due to their copying and passing of knowledge, it gave us a base to come from and without that. we would have little hope.
We did not even "rediscover" ancient Greek works until 1492 (test your mind and see if you can make that connection), and that was largely due in part to Christians pushing to recapture a believed holy site: the burial site of Saint James, beginning with the Camino de Santiago de Compostela in Compostela Spain.
And without the Irish, we as a civilization would not have had the organized religion to fight the Moors, having reverted back to largely pagan customs. You really should learn more about history.
This was more a book review than an intelligent, educated, articulate article of history and the question posed, and a poor book review at that.