Complex sentence: Under the leadership of Pierre Bédard, the party began campaining for ministerial responsibility and the election of the Legislative Council, then appointed by an appointed British Governor, which it considered to be severely corrupted and hostile to the interests of the majority of the population.
Split into simpler sentences: Under the leadership of Pierre Bédard, the party began campaining for ministerial responsibility and the election of the Legislative Council. At that time, the council was appointed by an appointed British Governor, which the "Parti canadien" considered to be severely corrupted and hostile to the interests of the majority of the population.