Today, 26th December, is the feast of St Stephen, the first recorded martyr of the Christian Church. It is a public holiday in Ireland and Catalunya. People often remember it, however, as the setting of the carol Good King Wenceslaus.
The Wenceslaus is question was the Duke of Bohemia, now part of the Czech Republic. In the Czech language his name was Vaclav. He lived in the 10th Century and was murdered. The Christmas carol does not contain historical material. It was published in 1853. It may have been based on an original poem by V.A. Svoboda. When it appeared in English, critics said it would not last long.
There is a tradition that knights are sleeping under Mount Blanik in the Czech Republic. It is said they will awaken and defend the Czechs when the need arises. In Wenceslaus Square, Prague, there is a statue of Wenceslaus and it is said this will come to life and lead the Czechs.