national leader vs Oliver Cromwell

national leader and Oliver Cromwell both are nouns.

Word	Noun	Adjective	Verb	Adverb
national leader	Yes	No	No	No
Oliver Cromwell	Yes	No	No	No

national leader (noun)	Oliver Cromwell (noun)
a person who is a respected leader in national or international affairs	English general and statesman who led the parliamentary army in the English Civil War (1599-1658)