All the cathedrals across Europe were built in the space of about 200 years, at the height of the crusades. They look expensive, but they were actually money machines.
Whilst there may have been an element of religious fervour to them, they were also a way of demonstrating power to potential enemies and the illiterate masses. You find pragmatism at the root of almost all high morals. If you dig deep enough, though, you find economics.
The Pillars of the Earth, by Ken Follet, is a novel about the building of a fictional British cathedral by a brilliant historian. He uses his characters to show how the cathedral building era across Europe, which lasted almost exactly 200 years, drew so many skilled workers, and so many support workers from the surrounding countryside to feed and clothe and entertain them, that entire cities grew up around the building site. It would remain a work in progress for generations until completed. A flourishing throng of people, where young apprentices could train and junior tradesmen could cut their teeth in business, was bound to turn into a stimulting environment where academic learning would flourish and innovation in all areas of human endeavour would be nurtured.
The wealthy people of the growing town donated to keep the building work going, since it was their bread and butter, and to be remembered. In Northern Europe, the richest would pay a high price to be buried inside the cathedral and be a part of it forever; although southern Europeans (who, to this day, bury their dead in the Roman style necropolis out of town) find this practice astonishing and gruesome.
By the time the cathedral was finished, the stone masons, carpenters and other skilled workers would integrate into the, by then, very wealthy city, or sometimes move on to teach their architectural skills at a new cathedral building project. Although we nowadays define a city as a town wtih a cathedral in it, it really worked the other way around. The cathedral made the city, not the city the cathedral.
When the Normans conquered Sicily, they managed to grab a prize which was one of the richest jewels in Europe, with flourishing pottery, pasta and other industries. They wanted to make it even better, though, and above all, they wanted to fill it with Christian wealth, to show everyone that their god was the most powerful and the most beneficent. So they began probaby the most prolific church and cathedral building programme that Europe has ever seen in such a small piece of land.
So essentially, building cathedrals was the medieval way to trigger a massive boost to the economy and industry. Stories of unfinished cathedrals are stories of tragic economic failure.
I suspect ancient Greek temples were a similar community phenomenon, and it makes me wonder what went wrong at Segesta. It is an ancient Greek temple in Sicily that still stands perfectly, but was never finished.
Sicily has so many cathedrals from this era, it is hardly a surprise it became the richest part of Europe at that time. And it is hardly surprising to me that the population revelled in the glory of God, when one looks at all the wealth and material reward their religious activities brought them.
Cathedrals in Sicily
For a full list of Sicily’s fabulous cathedrals, look at this Wikipedia article. It’s in Italian but even if you don’t speak it, you can see the list and photos.