mother country vs motherland

mother country and motherland both are nouns.

Word	Noun	Adjective	Verb	Adverb
mother country	Yes	No	No	No
motherland	Yes	No	No	No

As nouns, mother country and motherland are synonyms defined as:

Other synonyms of mother country include country of origin, fatherland, homeland, native land.

mother country (noun)	motherland (noun)
the country where you were born	the country where you were born