before vowels often is-, word-forming element meaning "equal, similar, identical; isometric," from Greek isos "equal to, the same as; equally divided; fair, impartial (of persons); even, level (of ground)," as in isometor "like one's mother." In English used properly only with words of Greek origin; the Latin equivalent is equi- (see equi-).
1530s, "civil organization;" 1640s, "an organized human society or community, body of persons forming a community governed according to a recognized system of government," from French politie (early 15c.) or directly from Late Latin polita "organized government" (see policy (n.1)).
<a href="https://www.etymonline.com/word/isopolity">Etymology of isopolity by etymonline</a>
Harper, D. (n.d.). Etymology of isopolity. Online Etymology Dictionary. Retrieved $(datetime), from https://www.etymonline.com/word/isopolity