During the fragmentation period, both lands of Lesser Poland were frequently ruled by the same prince. Among them were Bolesław IV the Curly, Mieszko III the Old, Casimir II the Just, Leszek I the White, Bolesław V the Chaste, Leszek II the Black, Władysław I the Elbow-high, and King of Bohemia, Wenceslaus II of Bohemia, who united Lesser Poland in 1290/1291. The province was pillaged during the Mongol invasion of Poland, when a combined army of Kraków and Sandomierz was destroyed by Baidar in the Battle of Chmielnik. The loss was so heavy that Norman Davies wrote: "At Chmielnik, the assembled nobility of Małopolska perished to a man." During their 1241, 1259, and 1287 invasions, the Mongols burned major cities of Lesser Poland, killing thousands of people. Furthermore, the province, especially its northeastern part, was often raided by the Lithuanians, Rusyns, Yotvingians, and Old Prussians. The city of Lublin suffered most frequently – among others, it was burnt by the Rusyns in 1244, the Lithuanians 1255, the Prussians in 1266, and the Yotvingians in 1282. Another center of the province, Sandomierz, was destroyed by the Tartars in 1260, and burnt by the Lithuanians in 1349.