"life at ease," by 1902 (as Reilly), popularized in U.S. during World War I; it seems to have been military slang initially, sometimes said to trace to various songs but none of that title has been found.
as an answer, "nothing, none," 1789, from German nix, dialectal variant of nichts "nothing," from Middle High German nihtes, from genitive of niht, nit "nothing," from Old High German niwiht, from ni, ne "no" (from PIE root *ne- "not") + wiht "thing, creature" (compare naught). By extension, as an adverb, "no."
mid-14c., nōn-schench, "slight refreshment of food and/or liquor taken at midday," originally taken in the afternoon, from none "noon" (see noon) + shench "draught, cup," from Old English scenc, related to scencan "to pour out, to give to drink," cognate with Old Frisian skenka "to give to drink, German, Dutch schenken "to give." Compare luncheon.
"notwithstanding," early 14c., neuer þe lesse; as one word from mid-14c., neuerþeles. The sense of never here is "not at all; none the," as in unmerged expressions such as never the wiser, never the worse. In the same sense Middle English also had never-less (early 14c.), neverthelater (c. 1200), never-later (late 14c.).