One of the oldest military vexillological relics preserved in our country is a painted Bavarian Catholic League cavalry flag of Maxmilian I, Prince-elector of Bavaria. Under this flag the catholic cavalry participated in the Battle of White Mountain in November 1620 and was most likely also used, after the adaptation and addition of the year and Latin motto “IN HOC SIGNO VINCAM” (Under this sign I shall overcome) and calendar era, during the execution of the leaders of the Bohemian Revolt in the Old Town Square, June 21, 1621. the importance of the flag is enhanced by the fact that it is a war trophy obtained in the subsequent battles of the Thirty Years' War by burghers of Domažlice.