Proper noun
the Sonderbund
(historical) The Swiss cantons of Lucerne, Fribourg, Valais, Uri, Schwyz, Unterwalden, and Zug, all predominantly Catholic and governed by conservative administrations, and the subject of the Sonderbund War of 1847.
In 1912 he visited the Sonderbund exhibition in Cologne, where works by Pablo Picasso and post-Impressionists such as Vincent van Gogh and Paul Gauguin profoundly influenced his approach to art. Source: Internet
The Radicals, fearful of a Jesuit takeover, used their control of the national government and ordered the Sonderbund disbanded. Source: Internet
The Sonderbund was easily defeated in less than a month; there were about 130 killed. Source: Internet