France was the country that once ruled Indochina.
Brazil
Louisiana was once a French colony as well as Canada and Haiti.
it once was a colony of the Kingdom of Great Britain.
Australia was once a colony of Great Britain.
france
Portugal Portugal
Portugal. It's better to say 'colony of' rather than 'country of'.
Angola was once a Portugeuse colony. Portugal was therefore the mother country of Angola.
Because Gabon was once a colony of France.
The Spanish Empire qualifies as such.
Venezuela is the country you are referring to. It was once a Spanish colony and is one of the major oil exporters in the Western Hemisphere, with significant oil reserves.