We have some of those ...
Somalia = Somali
Ethiopia = Ethiopian
Madagascar = Merina
Also ...
Guatemala = Sorta is represented by the Maya but it could see it as a colonial culture.
What about
Indus Valley (middle east ast)
Chavin (south america)
Elam (middle dast)
Hopewell (north American)
Parthian (Europe)
Kushan (middle east)
Britannica (Europe) classical age Britain
Hispania (Europe) classical age spain
Mauryan (middle east) classical age India
Zapotec (north American)
Tang (Asia)
Ming (Asia)
Choson (Asia) middle age Korea
Kadiri (Oceania)
Srivijava (Oceania)
Swahili (Africa)
Mali (Africa)
Delhi (middle east)
Tiahuanaco (south America)
Chimu (south America)
Borneo (Oceania)
Batavia (Oceania)
Fiji (Oceania)
New Guinea (Oceania)
Scotland (Europe)
Nigeria a(Africa)
Dakota (north American) the Indians
Alaskan (north American) 19th century
Mohave (north American)
Kwakiutl (north American)
Chile (south America) 19th century
Gran Columbia (south America) it split to Columbia, Venezuela and Ecuador
Morocco (Africa)
Jamaica (south America)
British Raj (Asia) east India company British rule India
Rhodesia (Africa)
Sumatra (Oceania)
Angola (Africa)
Lebanon (middle east)
Iran (middle east)
Afghanistan (middle east) 20th century
European Union (Europe) 21st century
African Union (21st century
Taiwan (Asia) 21st century
Singapore (Asia) 21zt century
Hong Kong (Asia) 21st century
Saudi Arabia (middle east) 21st century
South Korea (Asia) 21st century
Tech Japan (Asia) 21st century version
United states (north American) 21st century version
Superpower China (Asia) l 21st century