Cascadia was never a country. It is a bioregion in the Pacific Northwest of North America that encompasses parts of the United States and Canada.
No Haiti is its own country. It was once a territory of France until it gained independence in 1804.
An enclave is a small part of a country that is entirely surrounded by the territory of another country. This results in the enclave being geographically separated from the main part of its own country.
Haiti is part of the country of Hispaniola, sharing the island with the Dominican Republic.
Texas was once a country known as the Republic of Texas before it joined the United States in 1845.
Texas was once an independent country before joining the United States as a state.
England
SLovenia
Philippines
Pakistan
Eastern part of Pakistan
Panama , once part of Columbia, is the country.
It's a Commonwealth country because it was once part of the British Empire.
Eritrea was once part of Ethiopa.
Mali.
It was once part of the United Kingdom. It is now and independent country, while Northern Ireland is still part of the United Kingdom.
The Netherlands. Belgium became an independent country on October 4, 1830. Prior to that it has changed hands many times. The Eastern part was once the Bishopric of Liege, which was part of Germany. The western part was once Burgundian, then the 'Spanish Netherlands', then the 'Austrian Netherlands'. Various parts were once French, and during the Napoleonic wars (up to 1815) the whole of what is now Belgium was part of France.
Samoa as a whole was once part of the United States. It is now split into Western Samoa and U.S. Samoa.