 Complete the following phrase:  In spite of the Byzantine victory, the Empire at this time had in fact been reduced to a few disconnected strips of land besides the city of Constantinople itself. It was also facing grave economic problems and severely lacked soldiers. Pius II promoted the affordable donation of cannon by European monarchs as a means of aid. Any new cannons after the 1422 siege were gifts from European states, and aside from these no other advances were made to the Byzantine arsenal. As such, the next Ottoman leader, Mehmed II, would be 