Gediminas's Cap (Lithuanian: Gedimino kepurė) was the most important regalia of the Lithuanian monarchs who ruled the Grand Duchy of Lithuania until the Union of Lublin in 1569. During the inaugurations of Lithuanian monarchs, Gediminas's Cap was placed on the monarch's heads by the Bishop of Vilnius in Vilnius Cathedral.
Its name comes from Grand Duke Gediminas (c. 1275–1341), the founder of the Gediminids dynasty and patrilineal ancestor of Lithuanian rulers from the Kęstutaičiai and Jagiellonian dynasties, and symbolized the dynasty's continuity. The cap is mentioned in 16th-century sources and was kept in the Vilnius Castle treasury. It is depicted as a round unsegmented headdress in an armorial compiled for Paweł Holszański. Since 1547 Gediminas's Cap was minted on Lithuanian coins above the coat of arms of Lithuania. Gediminas's Cap lost its significance following the Union of Lublin in 1569 which abolished a separate inauguration of the Lithuanian monarchs in Vilnius Cathedral.
