Arcadian adj.

mountainous district in central Peloponnesus, a Latinized form of Greek Arkadia, which is traditionally from Arkas (genitive Arkadas), son of Zeus, name of the founder and first ruler of Arcadia.

The idealized Arcadia of later pastoral romance, "the home of piping shepherds and coy shepherdesses, where rustic simplicity and plenty satisfied the ambition of untutored hearts, and where ambition and its crimes were unknown" [John Mahaffy, "History of Classical Greek Literature," 1880] seems to have been inspired by "Arcadia," a description of shepherd life in prose and verse by Italian Renaissance poet Iacopo Sannazaro, published in 1502, which went through 60 editions in the century. It is exemplified in English by Sir Philip Sidney's poem, published in 1590, and in Spanish by Lope de Vega's, printed in 1598. Classical Arcadia, Mahaffy writes:

was only famed for the marketable valour of its hardy mountaineers, of whom the Tegeans had held their own even against the power of Sparta, and obtained an honourable place in her army. It was also noted for rude and primitive cults, of which later men praised the simplicity and homely piety—at times also, the stern gloominess, which did not shrink from the offering of human blood. ["Rambles and Studies in Greece," 1887]

Poetic Arcady is from 1580s.

"native or inhabitant of the French colony of Acadia" in what is now the Canadian Maritimes, 1705, from Acadia, Latinized form of Acadie, French name of Nova Scotia, probably from Archadia, the name given to the region by Verrazano in 1520s, from Greek Arkadia, then emblematic in pastoral poetry of a place of rural peace (see Arcadian); the name may have been suggested to Europeans by the native Micmac (Algonquian) word akadie "fertile land." The Acadians, expelled by the English in 1755, settled in large numbers in Louisiana, and were known there as Acadians by 1803 (see Cajun, which is a corruption of Acadian).