Armée de l'Est

The Armée de l'Est (Army of the East; German - Ostarmee; also Second Loire Army; nicknamed the 'Bourbaki army' after its first commander General Charles Denis Sauter Bourbaki) was a French army which took part in the Franco-Prussian War of 1870–71. It was formed towards the end of the war out of the remains of the Loire Army, paramilitaries (Freischärlern) and new recruits.

The task of the army was intended to be the relief of the besieged fortress of Belfort and the interruption of the German supply lines. However, it suffered a defeat at Belfort in the battle of the Lisaine. The retreat to the south went chaotically and slowly, and the army was surrounded in the area of Pontarlier, close to the Swiss border.

General Bourbaki was relieved of his duties and made a suicide attempt. The new commanding general, Justin Clinchant, requested military asylum in Switzerland. From 1 to 3 February 1871 87,000 men crossed the Franco-Swiss border at Les Verrières and were interned for six weeks. Hans Herzog (1819–1894), Swiss general during the border occupation 1870–71, oversaw the internment of the defeated army. The crossing of the Bourbakiarmee is shown on the Bourbaki Panorama in Lucerne.

Although General Herzog had, as best he could, placed contingents of the already partly demobilized army at the places where the French were crossing the border, these units probably would have had little chance against the German pursuers of the French, led by the German General Edwin von Manteuffel. And there was theoretically a motive for such an attack: Prussia had waived its rights to Neuenburg in the Neuenburgerhandel in 1856/57 after mediation by the European powers. Neuenburg, which was where the Bourbaki troops entered Switzerland, had been a Prussian principality until 1857.

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