The mobilization machinery of the North-German army had been elaborated from year to year, in accord with the changing conditions, by the combined exertions of the War Ministry and the General Staff. Every branch of the administration throughout the country had been kept informed of all it needed to know in this relation. The Berlin authorities had also come to a confidential understanding with the Chiefs of the General Staffs of the South-German States on all important points. The principle was established that Prussian assistance was not to be reckoned on for the defence of any particular point, such as the Black Forest; and that South Germany would be best protected by an offensive movement into Alsace from the middle Rhine, to be effectively supported by a large army massed there. That the Governments of Bavaria, Würtemberg, Baden and Hesse, to all appearance uncovering their own territories, were ready to place their contingents under the command of King William, proved their entire confidence in the Prussian leadership.
This understanding enabled the preparations which it entailed to be proceeded with. The train and march tables were worked out for each body of troops, with the most minute directions as to the respective starting-points, the day and hour of departure, the duration of the journey, the refreshment stations, and points of detrainment. In the locality of concentration cantonments were assigned to each Corps and Division, and magazines were established with due regard to the most convenient sites; and thus, when the stroke of war inevitably impended, there was required only the Royal signature to start the whole mighty movement in its smooth, swift course. Nothing needed to be changed in the directions originally given; it sufficed to follow the plans previously thought out and prepared.
The aggregated mobile forces were formed into three separate Armies, on the basis of an elaborate tabular statement drawn up by the Chief of the Prussian General Staff.
The Ist Army, under the command of General von Steinmetz, consisted of, in the first instance, only the VIIth and VIIIth Corps, with one Division of cavalry; 60,000 men all told. It was ordered to assemble at Wittlich and form the right wing.
The IInd Army, under the command of Prince Frederick Charles, consisted of the IIIrd, IVth, Xth, and Guard Corps, with two Divisions of cavalry. Assembling in the vicinity of Homburg and Neunkirchen, it was to form the centre, with a strength of 134,000 men.
The IIIrd Army, under the command of the Crown Prince of Prussia, consisted of the Vth and XIth Prussian, and the Ist and IInd Bavarian Corps, the Würtemberg and Baden Field Divisions, with one Division of cavalry. Its approximate strength was 130,000 men; it was to constitute the left wing, and to concentrate about Landau and Rastatt.
The IXth Corps, consisting of the 18th and the Hesse Divisions, was along with the XIIth Royal Saxon Corps to form a reserve of 60,000 men in front of Mayence, for the reinforcement of the IInd Army to a strength of 194,000 men.
The three Armies numbered together 384,000 men.
There still remained the Ist, IInd, and VIth Corps, numbering 100,000 men; but they were not at first included, as railway transport for them was not available for three weeks to come. The 17th Division and certain bodies of Landwehr troops were detailed to defend the coasts.
It is apparent that numerically the German armies were considerably superior to the French. Inclusive of the garrisons and reserves about one million of men and over 200,000 horses were on the ration list.