France is the oldest-formed European country. It did not break away from any other.
If a region wants to break away from the rest of the country, it would typically involve a process known as secession. Secession is the act of formally withdrawing from a political entity such as a country or state. This process can be complex and contentious, often involving legal, political, and social challenges.
India
Uhh.........none.
From any foreign country !
Spain
1 state
The province of Quebec, driven by the Parti Quebecoi, has tried to break away from Canada to form there own country.
to leave the official term is secede
expatriate ... at least in some circumstances.
Hawai`i is part of the US, even though it is 2,390 miles away from California.
America broke away from England which is part of Great Britain.