Complex sentence: Previously the tsar had been seen as the champion of the people: in dire situations, the masses would appeal to the tsar, traditionally through a petition, and the tsar would respond to his people promising to set things right.
Split into simpler sentences: Previously the tsar had been seen as the champion of the people. In dire situations, the masses would appeal to the tsar, traditionally through a petition, and the tsar would respond to his people promising to set things right.