However, in practice, there would be enormous popular and political resistance if the central government tried to revoke the autonomy of a region.
As in Spain, some politicians and political parties in the country, especially those that express regionalist ideology, favor the establishment of a federal system in Italy.
There are also several federations in Europe, notably Germany, Austria and Belgium but also Bosnia and Herzegovina, Russia[dubious – discuss], Switzerland and debatably the Kingdom of the Netherlands (not to be confused with the Netherlands, which forms one of its constituent countries though overwhelmingly the most important one; this last also could be considered a regional state, according their provincial government duties).
Several European countries (namely France, the Netherlands, and the United Kingdom) have overseas territories in the Caribbean that have devolved governments of their own.
Additionally, some regions such as Western New Guinea and Aceh have more autonomy because of their unique and often fractious relationship with the national government.
The Republic of China, which has ruled Taiwan since 1945, can be considered as a regional state as there are a number of counties and cities that are self-governing according to the Local Government Act.
New Zealand is divided into sixteen regions (Māori: Ngā takiwā) for local government purposes.
They are common because all of the continent's countries except for Liberia and Ethiopia came into existence in the 20th or the 21st centuries and so were not constrained by old constitutional structures in setting up their governments.
South Africa is a regional state divided into a number of provinces, all of which have their own elected provincial legislature and Premier and exercise significant degrees of authority.