Pastoral
A pastoral is "a deliberately conventional poem expressing an urban poet's nostalgic image of the peace and simplicity of the life of shepherds and other rural folk in an idealized natural setting" (Abrams 202).
The name derived from the Latin word pastor, shepherd.
The adjective "pastoral" can be applied to other genres of literatures that take up the motifs of life in the countryside.
Examples from the Renaissance include Edmund Spenser's Shepherd's Calendar (1579, a collection of pastoral poems) and Philip Sidney's Arcadia (1581-84, a pastoral romance).
M. H. Abrams: A Glossary of Literary Terms. Seventh Edition. New York et al.: Harcourt Brace, 1999.