Belgium and the Franco-Prussian War

Though not actually a belligerent in the Franco–Prussian War (1870–71), Belgian society and politics were heavily affected by the conflict, and in particular the fear of invasion by either side. The mobilization of the army in 1870 highlighted the inadequacies of the Belgian military and led to reform of the system of conscription (and the abandonment of the system of Remplacement) and a programme of re-fortification towards the end of the 19th century which would greatly influence the early phases of the First World War.

It was assumed by many that in the event of war between France and Prussia, an attack through Belgium by either side might reasonably be the first act, particularly after Emperor Napoleon III's attempt to annex Luxembourg in 1867.

Indeed, in the early part of the war, French Marshal Canrobert brought an entire Army Corps (4 infantry divisions) to Châlons-sur-Marne in northern France as a reserve and to guard against any Prussian advance through Belgium.

So when news of the declaration of war was received, the Belgian government of Jules d'Anethan (installed only two weeks before the war's outbreak), under King Leopold II, feared that it might be overrun. The gold reserves of the National Bank were hurried to the National Redoubt at Antwerp before the news became public. When this leaked out, it caused panic.

The Belgian army was called up on the 15 July, the same day that both French and German armies mobilised. The Belgian troops were divided into two armies; the Army of Antwerp (15,000 men) was tasked with guarding the fortresses at Antwerp and across Belgium while the Army of Observation (55,000 men) was tasked with defending the national borders.

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