Ladislaus I of Hungary
In the 13th century King Béla III declared the double cross (ex post) a symbol of Saint Ladislaus (King Ladislaus I of Hungary). In 1386, it became part of the coat of arms of the house of Jagiello, because Grand Duke of Lithuania Jogaila took over the alleged coat of arms of Saint Ladislaus when being baptized as Ladislaus (Wladyslaw). By means of the Jagiellons, the symbol also got into the coat of arms of Lithuania.