 The event was first labelled the "Peterloo massacre" by the radical "Manchester Observer" newspaper, in a bitterly ironic reference to the bloody Battle of Waterloo, which had taken place four years earlier.Historian Robert Poole has called the Peterloo Massacre 'the bloodiest political event of the 19th century in English soil', and 'a political earthquake in the northern powerhouse of the industrial revolution'.The London and national papers shared the horror felt in the Manchester region, but Peterloo's immediate effect was to cause the government to pass the Six Acts, which were aimed at suppressing any meetings for the purpose of radical reform.