Nation ends in -tion, the commonest Latin suffix in English, and it came in about 1300 through Old French nacion and directly from Latin nationem. The Latin literally means "that which has been born," from nasci, "to be born" — the same root as native, nature, innate and pregnant.
That birth metaphor is the whole word. A nation was first a race of people with a common ancestry and language, which is a claim about descent rather than politics. English still uses it in that broad ethnic sense and in the narrower modern one of a political society with a government and citizens, and the two senses have been quietly at odds for centuries — most arguments about what a nation is are arguments about which of the two you mean. The -tion ending is worth knowing on its own: nation, question, action, direction all announce a Latin abstract noun.
nation (n.) c. 1300, nacioun , "a race of people, large group of people with common ancestry and language," from Old French nacion "birth, rank; descendants, relatives; country, homeland" (12c.) and directly from Latin nationem (nominative natio ) "birth, origin; breed, stock, kind, species; race of people, tribe," literally "that which has been born," from natus , past participle of nasci "be born" (Old Latin gnasci ), from PIE root *gene- "give birth, beget," with derivatives referring to procreation and familial and tribal groups. The word is used in English in a broad sense, "a race of people, an aggregation of persons of the same ethnic family and speaking the same language," and also in the narrower sense, "a political society composed of a government and subjects or citizens and constituting a political unit; an organized community inhabiting a defined territory within which its sovereignty is exercised." In Middle English it is not easy to distinguish them, but the "political society" sense emerged by 16c., perhaps late 14c., and it has gradually predominated. The older sense is preserved in the application of nation to the native North American peoples (1640s). Nation-state "sovereign country the inhabitants of which are united by language, culture, and common descent" is from 1918. A nation is an organized community within a certain territory; or in other words, there must be a place where its sole sovereignty is exercised. [Theodore D. Woolsey, "Introduction to the Study of International Law," 1864] Nation-building "creation or development of a new nation" is attested by 1868, in reference to modernization of China and Japan. Also used by 1871 in American English in reference to the U.S., founders, homesteaders, or working farmers. Our nation building began with our revolution, and ever since that time we have been continuing the great work. Nor should our activity cease, for an indolent people show signs of decay, and what is true of a people is true of a nation. [report on lecture by John W. Cummings, "Boston Globe," Feb. 4, 1886] It was used in 1879 in the "Cherokee Advocate" newspaper with reference to that people. also from c. 1300
nation came in through Latin, and its spelling follows that family's conventions.
How that family writes these sounds
| the abstract endings | -tion/-sion, -ity, -ous, -ate, -al, -ive, -arynation, gravity, various, create, legal, active |
| /ʃ/ buried inside a long formal noun | ti, not shnation, partial |
What gives it away on the page
| -tion/-sion, -ity, -ous, -ate, -al, -ive, -ary | The standard Latin suffix set, usually stacked on a Latin root.nation, gravity, various, create, legal, active |
Placing it without the spelling
| abstraction, law, administration — words written before they're spoken | Latinnation, gravity, various, accept |