In the book "Ideas: A History of Thought and Invention, from Fire to Freud," the author Peter Watson reveals how religions have been consolidating rituals and customs of other religions to convert believers into their own religion.
The book touches on thousands of historical facts but the one that interested me the most was the fact that the religions of today are based in past beliefs from older religions. Even more astonishing, we celebrate rituals todays that came from old celebrations from religions around the world. Those old celebrations are based in certain cases to a physical event (e.g. solstice) and not to the historical facts that are religions try to sell us (e.g. birth of Christ).
The consolidations of beliefs and celebrations into very few religions nowadays makes me belief that the first industry to be consolidated in the world was relgion. The first consolidator and "multinational" was Catholicism.