The folklore festivals keep gaining in popularity every year. The international folklore festival, Baltica, is also well known. Since the 14th century, the 24th of June has been celebrated in observance of the Feast of St John, or Rasa Day. Lithuanian arts became particularly abundant under the conditions of the independent state, between the two world wars. Lithuanian stained-glass art, paintings and sculpture may be ascribed to the most outstanding manifestations of that period.
Religious art is an important part of Lithuanian art, too.
Most examples of this art have survived within churches of all styles and epochs. Another aspect of religious art can be found in the Lithuanian countryside tradition. The first book in Lithuanian, the Evangelical Lutheran Catechism, was published in Prussia in 1547 by Martynas Mazvydas. This is how the Lithuanian language came to be written in the Latin alphabet. During the 16th-18th centuries, Lithuanian writing gained strength.