The invader's objective with respect to central France was Bourges, the old capital of Berry, renowned for its ordnance and ammunition works, and, in the days when the troops of our Henry V overran France, the scene of Charles VII's retirement, before he was inspirited either by Agnes Sorel or by Joan of Arc. To enable an army coming from the direction of Paris to seize Bourges, it is in the first instance necessary--as a reference to any map of France will show--to secure possession of Orleans, which is situated at the most northern point, the apex, so to say, of the course of the Loire, and is only about sixty-eight miles from Paris. At the same time it is advisable that any advance upon Orleans should be covered, westward, by a corresponding advance on Chartres, and thence on Châteaudun. This became the German plan, and whilst a force under General von Wittich marched on Chartres, Von der Tann's men approached Orleans through the Beauce region.
From the forest of Dourdan on the north to the Loire on the south, and from the Chartres region on the west to the Gatinais on the east, this great grain-growing plateau (the scene of Zola's famous novel "La Terre") is almost level. Although its soil is very fertile there are few watercourses in Beauce, none of them, moreover, being of a nature to impede the march of an army. The roads are lined with stunted elms, and here and there a small copse, a straggling farm, a little village, may be seen, together with many a row of stacks, the whole forming in late autumn and in winter--when hurricanes, rain, and snow-storms sweep across the great expanse--as dreary a picture as the most melancholy-minded individual could desire. Whilst there is no natural obstacle to impede the advance of an invader, there is also no cover for purposes of defence. All the way from Chartres to Orleans the high-road is not once intersected by a river. Nearly all of the few streams which exist thereabouts run from south to north, and they supply no means of defence against an army coming from the direction of Paris. The region is one better suited for the employment of cavalry and artillery than for that of foot-soldiers.
The Chartres country is better watered than Beaude. Westward, in both of the districts of Perche, going either towards Mortagne or towards Nogent-le-Rotrou, the country is more hilly and more wooded; and hedges, ditches, and dingle paths abound there. In such districts infantry can well be employed for defensive purposes. Beyond the Loir--not the Loire-- S.S.W. of Chartres, is the Pays Dunois, that is the district of Châteaudun, a little town protected on the north and the west by the Loir and the Conie, and by the hills between which those rivers flow, but open to any attack on the east, from which direction, indeed, the Germans naturally approached it.