Complex sentence: When the king summoned a great council in October, several of the earls refused to meet due to Gaveston's presence, and at the parliament of February the next year, Gaveston was ordered not to attend.
Split into simpler sentences: When the king summoned a great council in October, several of the earls refused to meet due to Gaveston's presence. At the parliament of February in the following year, Gaveston was ordered not to attend.