founding father of a country
Refers to a person who played a central role in establishing a nation. Often used in historical or political contexts.
George Washington is regarded as one of the founding fathers of the United States.
The politician is respected as the founding father of his country.
父 means 'father' in a general sense; in 建国の父 it is used metaphorically for a founder.
A compound of 建国 (founding of a nation) + の (possessive particle) + 父 (father). The phrase is a calque from English 'founding father' and is used in similar historical contexts.