Political map of Europe & the Mediterranean 29 November 1850 (Humiliation of Olmütz): The Erfurt Union did not last long. In autumn the Electorate of Hesse, which formed the crucial bridge between Prussia's eastern and western possessions, went into revolt and the Elector called for support from the Diet of the German Confederation, the entity the Union had supposedly replaced. For a few months, forces of the Prussian-dominated Union and the Austrian-dominated Confederation faced off over Hesse, but in the end Prussia gave in, abandoning the Erfurt Union at the Treaty of Olmütz.