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-building "creation of a new nation" is attested by 1907 (implied in nation-builder). 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]
1814, coined by English polymath Thomas Young (1773-1829) and first used in an article in the "Quarterly Review," from Indo- + European. "Common to India and Europe," specifically in reference to the group of related languages and to the race or races characterized by their use. William Dwight Whitney ("The Life and Growth of Language," 1875) credits its widespread use to Franz Bopp.
The alternative Indo-Germanic (1835) was coined in German in 1823 (indogermanisch), based on the two peoples then thought to be at the extremes of the geographic area covered by the languages, but this was before Celtic was realized also to be an Indo-European language. After this was proved, many German scholars switched to Indo-European as more accurate, but Indo-Germanic continued in use (popularized by the titles of major works) and the predominance of German scholarship in this field made it the popular term in England, too, through the 19c. See also Aryan and Japhetic.
Indo-Aryan (1850) seems to have been used only of the Aryans of India. Indo-European also was used in reference to trade between Europe and India or European colonial enterprises in India (1813).
the hypothetical reconstructed ancestral language of the Indo-European family, by 1905. The time scale of the "language" itself is much debated, but a recent date proposed for it is about 5,500 years ago.
"government by a protector," 1690s, in reference to the government by the Cromwells as Lords Protector (1653-59), from protector + -ate (1). Protectorship was used in 1456 in reference to the office of the Duke of York as protector during the mental incapacity of Henry VI.
From 1795 as "occupied territory of another nation;" by 1836 as "a relation assumed by a stronger nation (generally European) toward a weak one," "whereby the former protects the latter from hostile invasion or dictation, and interferes more or less in its domestic concerns" [Century Dictionary]. Extended by 1860 to "state or territory (usually tribal) placed under the protection of a major power."