The purpose of the invasion was to loot the divided Kingdom of Poland (see Testament of Bolesław III Krzywousty), and to weaken Duke of Kraków Bolesław V the Chaste, whose province, Lesser Poland, began a process of fast development. According to the Mongol plan, the invaders were to enter Lesser Poland east of Lublin, and head towards Zawichost. After crossing the Vistula, the Mongol army was to break into two columns, operating north and south of the Holy Cross Mountains. The columns were to unite near Chęciny, and then head southwards, to Kraków. Altogether, Mongol forces under Boroldai were 30,000 strong, with Ruthenian units of King Daniel of Galicia, his brother Vasilko Romanovich, Kipchaks and probably Lithuanians or Yotvingians. The province that they had invaded was completely destroyed with rich loot taken. Some 10,000 Poles were taken with the invaders as slaves. The success of the Golden Horde was complete, as they managed to destroy an anti-Mongol alliance, and completely subjugate the Kingdom of Galicia–Volhynia.
