Glarus Süd is a municipality in the Swiss canton of Glarus. It comprises the upper Linth valley, and the entire Sernf valley, and includes the villages of Betschwanden, Braunwald, Diesbach, Elm, Engi, Haslen, Hätzingen, Leuggelbach, Linthal, Luchsingen, Matt, Mitlödi, Nidfurn, Rüti, Schwanden, Schwändi and Sool.

The canton of Glarus is a canton in east central Switzerland. The capital is Glarus. The population speaks a variety of Alemannic German. The majority of the population (81%) identifies as Christian, about evenly split between Protestants and Catholics.