It has been argued that Galeazzo II's reign was tyrannical. The use of violent tactics, assistance from exiled opponents, expansionist ideals which challenged the papacy at the expense of subjects, and seizing power over regions without permission of the rightful overload, empire or papacy were traits found within Galeazzo's rule. An example of his alleged tyranny was when Galeazzo II unrightfully seized the city-state, Pavia, on 13 November 1359. In order to weaken the Visconti influence, emperor Charles IV gave vicarite of Pavia to Giovanni Palaeologus II. After a rebellion led by the Augustinian friar Jacopo Bussolari broke out, calling for the city's independence, Gaeleazzo recognized Pavia's vulnerability and seized the city-state for himself. Though the citizens resisted his domination, they eventually gave in to Galeazzo's control. Throughout his rule, Galeazzo was also accused of heresy, seeking to kill the pope, and fighting to claim lordship of all of Italy, which support the allegations of tyrannical rule.