After doing a bit of research (I know nothing of the arts), it appears that a revival of the medieval style of art happened in the late 1800's, particularly in liturgical publications.
There's so much that can be said about this entire phenomenon. The western world rebelled against the classicism and the worship of Greece and Rome that was fostered from the Enlightenment until the fall of Napoleon. From this point on, you encounter romantic movements, medieval and Gothic revivalism. I'd say neo-medievalism really got into full swing by the 1830's. Some examples:
-Sir Walter Scott's
Ivanhoe, published in 1820, a novel set in 12th century England that popularized the tales of Robin Hood and "good King Richard". It's hard to imagine, but before Ivanhoe, the English didn't think much of "merry ole England" and even thought King John was a good ruler, punished by the Pope for being a sort of proto-Protestant!
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The Eglinton Tournament of 1839, a massive jousting re-enactment in Scotland that attracted 100,000 spectators. Some Victorian nobles around this time period staged medieval-themed parties or masquerades.
-The revival of Gothic architecture is a big one. The architect
Augustus Pugin, who designed much of the current Parliament building in London (Westminster Palace), was a giant of the period. He insisted that Gothic architecture was the one true Christian style. Meanwhile, the French Viollet-le-Duc was responsible for restoring the
Sainte-Chapelle in Paris to its current appearance. Meanwhile, the Germans were enthralled by the music of Wagner and "Mad King" Ludwig II of Bavaria was designing medieval fantasy castles like
Neuschwanstein.
-After the Middle Ages, Saint Joan of Arc was not popular in France again until after the age of Napoleon. Her cause of canonization began during the mid-1800's thanks to the influence of the romantic medievalists.
-Dom Gueranger and the abbey of Solesmes spearheaded the revival of Gregorian chant during the romantic period, which had been effectively dead beforehand. The groundwork for the Liber Usualis and other chant books began in the mid-1800's.
-Meanwhile, the Church of England was experiencing the
Oxford Movement, which attempted to reconcile Anglicanism with medieval Christianity and make it more "catholic". Its most famous activist was John Henry Newman, who as we all know eventually swam the Tiber and became a cardinal.