What has sparked the interest in ancient national epics in late 18th century?

by confused_druze

I've been looking at the first modern (re-)discovery, copy and printing dates of the various national epics and couldn't help but to recognize a craze for medieval poetry in the late 18th century:

1779 Spain - El Cantar de Mio Cid

1782 Germany - The Song of the Nibelungs

1786 England - Beowulf

1792 Russia - the Song about Igor's Campaign

What caused the different publishers in Europe to dig up things that hitherto were considered to be utterly tasteless when compared to ancient examples?

There was a second wave during the springtime of nations with the Finnish Kalavela, the French Song of Roland or the Dutch Lion of Flanders; but here it was already perceived as a part of the nation building process. What has caused the initial wave?

VestureOfSilence

To establish a nation's identity as being highly cultured since time out of mind, I suppose, true or false.