Mantinea vs Mantineia

Mantinea and Mantineia both are nouns.

Word	Noun	Adjective	Verb	Adverb
Mantinea	Yes	No	No	No
Mantineia	Yes	No	No	No

As nouns, Mantinea and Mantineia are synonyms defined as:

Mantinea and Mantineia: the site of three famous battles among Greek city-states: in 418 BC and 362 BC and 207 BC

Mantinea (noun)	Mantineia (noun)
the site of three famous battles among Greek city-states: in 418 BC and 362 BC and 207 BC	the site of three famous battles among Greek city-states: in 418 BC and 362 BC and 207 BC