From the CIA website:

CENTRAL AMERICA AND CARIBBEAN :: SAINT VINCENT AND THE GRENADINES
PAGE LAST UPDATED ON JANUARY 12, 2017

Resistance by native Caribs prevented colonization on Saint Vincent until 1719. Disputed between France and the UK for most of the 18th century, the island was ceded to the latter in 1783. Between 1960 and 1962, Saint Vincent and the Grenadines was a separate administrative unit of the Federation of the West Indies. Autonomy was granted in 1969 and independence in 1979.

Flag of St Vincent and the Grenadines:

They are kind of like Turks and Caicos in the Caribbean: one territory name defines multiples islands.