During the Chartist movement popular radicalism was relatively weak in France, only spreading extensively under the Second Republic when Chartism entered its terminal decline. This was partly due to the longer history of this kind of radicalism in Britain and its absence in France before 1830, but the crucial factor in the contrasting natures of British and French radical activity lay in the differences in the two regimes. These differences explain the apparently greater revolutionary and more violent character of radical action in France. The Chartist movement achieved a greater level of national unity and organization, and since it lasted longer it also changed over time. There was much common ground in the radical ideas on both sides of the Channel and in the radical movements' reliance on mobilizing local and often informal groups into temporary wider alliances and organisations. The differences between Britain and France thus lay mainly in the forms radical activity took, and these depended mainly on the differences in the political situations in the two countries, especially the more stable political system and greater freedom of Britain and the extent of open political campaigning there.