in-country n.

a Middle English merger of Old English in (prep.) "in, into, upon, on, at, among; about, during;" and Old English inne (adv.) "within, inside," from Proto-Germanic *in (source also of Old Frisian, Dutch, German, Gothic in, Old Norse i), from PIE root *en "in." The simpler form took on both senses in Middle English.

Sense distinction between in and on is from later Middle English, and nuances in use of in and at still distinguish British and American English (in school/at school). Sometimes in Middle English shortened to i.

The noun sense of "influence, access (to power or authorities)," as in have an in with, is first recorded 1929 in American English. to be in for it "certain to meet with something unpleasant" is from 1690s. To be in with "on friendly terms with" is from 1670s. Ins and outs "intricacies, complications of an action or course" is from 1660s. In-and-out (n.) "copulation" is attested from 1610s.

mid-13c., "(one's) native land;" c. 1300, "any geographic area," sometimes with implications of political organization, from Old French contree, cuntrede "region, district, country," from Vulgar Latin *(terra) contrata "(land) lying opposite," or "(land) spread before one," in Medieval Latin "country, region," from Latin contra "opposite, against" (see contra-). The native word is land.

Also from c. 1300 as "area surrounding a walled city or town; the open country." By early 16c. the word was applied mostly to rural areas, as opposed to towns and cities. Meaning "inhabitants of a country, the people" is from c. 1300.

INTERVIEWER [Steve Rossi]: "Would you say you're the best fighter in the country?

PUNCH-DRUNK BOXER [Marty Allen]: "Yeah, but in the city they murder me." 

As an adjective from late 14c., "peculiar to one's own country (obsolete); by 1520s as "pertaining to or belonging to the rural parts of a region," typically with implications of "rude, unpolished."

Country air "fresh air" is from 1630s. First record of country-and-western as a music style is by 1942, American English. Country music is by 1968. Country club "recreational and social club, typically exclusive, located in or near the country" is by 1886. Country mile "a long way" is from 1915, American English. Country-mouse is from 1580s; the fable of the mouse cousins is as old as Aesop. Country road "road through rural regions" is from 1873.