If the Nineteenth Century was dominated by the increasing scope and power of Europe's colonial system, The Twentieth saw the destruction of the same.
Decolonization is often equated with the end of colonial rule, but this is much too narrow. It is far more useful to think of it as the demolition of a Europe-centred imperial order in which territorial empire was interlocked with extraterritorial ‘rights’. The bases, enclaves, garrisons, gunboats, treaty ports and unequal treaties (as in Egypt or China) that littered the Afro-Asian world were as much the expression of this European imperialism as were the colonies and protectorates coloured red, blue, yellow or green on the old imperial maps. So was the assumption that intervention was justified by the general failure of non-European states to reach the civilizational standard that European visitors were entitled to expect. This imperial ‘order’ imagined a cultural hierarchy in which the progressive capabilities of North West European (and Euro-American) societies were contrasted with the (sometimes picturesque) ‘stationary state’ in which non-Western cultures were presumed to be stuck. It also expected, and where possible enforced, an economic division of labour in which the capital, manufactures and technical skills of the imperial-industrial world were exchanged for the raw materials and foodstuffs of the non-Western countries.
Most, if not all, of this global ‘regime’ was quickly demolished in the two decades that followed the Second World War...
Darwin, John (2010-08-08). After Tamerlane (pp. 441-442). Bloomsbury Publishing Plc. Kindle Edition.
The Soviet empire was enough more durable to last almost four decades after the war.