peninsularity
/pɪˌnɪnsjʊˈlarɪti/noun
1A narrow-minded character or outlook, of the sort supposed to result from living on a peninsula and thus having limited contact with other peoples; mental or intellectual isolation akin to insularity.
2The fact of being a peninsula; peninsular nature.
Origin
Late 19th century; earliest use found in Grant Allen (1848–1899), writer on science and novelist. From peninsular + -ity, after insularity.