Coinciding with the Millennium Jubilee of the Czech patron saint St. Wenceslas (Duke of Bohemia), the Gothic reconstruction work for St. Vitas Cathedral in Prague was completed in 1929. The new stained glass window, designed by Mucha, was installed in the north nave in 1931.

The window portrays the boy St. Wenceslas with his grandmother St. Ludmila in the centre, surrounded by episodes from the lives of Saints Cyril and Methodius who spread Christianity among the Slavs. The image of Slavia is also included below Christ, and as an emblem of Slavia Bank who funded the stained glass window.