Behind this were two young princes, Pedro and Miguel. The brothers were very alike in many ways, but differed in their way of thinking and their ideals.
Pedro had brought about the Independence of Brazil, which he had turned into an Empire, and had granted a Constitution. He was then called upon to defend the same constitutional and liberal interests in the old kingdom of Portugal, where people, especially in the cities, were seething with the consequences of the French invasions, and the abusive presence of English troops.
Miguel, on the other hand, was a staunch supporter of a more traditional form of government, in line with the supporters of the old regime, who had come back in force after the fall of Napoleon. In Portugal, ordinary people, especially in rural areas, but also many intellectuals who had absolutist monarchic views, were totally on his side.
Miguel seized power in Lisbon, in June, 1828, and suddenly many defenders of liberal and constitutional ideals began to arrive in Terceira and establish themselves there, supported locally by a determined liberal nucleus, despite the knowledge that the general population supported Miguel.