 Throughout the period from Casimir the Great ( r . 1333 – 1370 ) to Stanislaus Augustus , Polish crown jewels were commonly believed to date back to the times of Boleslaus the Brave . This conviction helped maintain a sense of continuity of Polish statehood and provide legitimacy for the nation 's kings , implicitly making each Polish monarch a successor of the ancient and glorious legacy of the first king of the House of Piast . Accordingly , the coronation sword took over the name and the legend of the original Szczerbiec . The corrosion @-@ induced slit in the blade became associated with the fabled szczerba , or notch that Boleslaus had purportedly made on his sword in Kiev . The power of tradition was so strong that when Stanislaus Augustus 's court painter , Marcello Bacciarelli , who had made detailed studies of Polish crown jewels , painted an imaginary portrait of Boleslaus the Brave , he chose to depict Szczerbiec so that its appearance agreed with legend rather than reality . The images of the coronation crown and sword are overall meticulously accurate , but Bacciarelli 's Szczerbiec lacks the slit and has a chipped edge instead . 
