Colonialism peaked in 19th century when countries doing it werent liberal democracies. Universal suffrage for men became thing only at the end of century. But widespread demands started in 1848. Before that voting was restricted to income/tax/property.
political system that emerged in the exact places colonialism benefitted represents a political system that emerged out of colonialism
Not all european liberal democracies had colonies. But it is true that those countries that had them, didn't decolonize after liberalization.
