The concept of the separation of church and state refers to the distance in the relationship between organized religion and the nation state.
The concept of separation has been adopted in a number of countries, to varying degrees depending on the applicable legal structures and prevalent views toward the proper role of religion in society. A similar but typically stricter principle of laïcité

Laïcité

French secularism, in French, laïcité is a concept denoting the absence of religious involvement in government affairs as well as absence of government involvement in religious affairs. French secularism has a long history but the current regime is based on the 1905 French law on the Separation of...

has been applied in France

France

The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...

 and Turkey

Turkey

Turkey , known officially as the Republic of Turkey , is a Eurasian country located in Western Asia and in East Thrace in Southeastern Europe...

, while some socially secularized countries such as Norway

Norway

Norway , officially the Kingdom of Norway, is a Nordic unitary constitutional monarchy whose territory comprises the western portion of the Scandinavian Peninsula, Jan Mayen, and the Arctic archipelago of Svalbard and Bouvet Island. Norway has a total area of and a population of about 4.9 million...

, Denmark

Denmark

Denmark is a Scandinavian country in Northern Europe. The countries of Denmark and Greenland, as well as the Faroe Islands, constitute the Kingdom of Denmark . It is the southernmost of the Nordic countries, southwest of Sweden and south of Norway, and bordered to the south by Germany. Denmark...

 and the UK

United Kingdom

The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

 have maintained constitutional recognition of an official state religion.