Their right rested on the Danube; and the village of Blenheim, close to its bank, was held by twenty-six battalions and twelve squadrons, all native French troops.
Their left was equally protected from attack by a range of hills, impregnable for guns or cavalry.

In the centre of their line, between their flanks, was the village of Oberglau, in and around which lay thirty battalions of infantry, among whom was the fine Irish regiments.
From Blenheim to Oberglau, and thence on to Lutzingen, at the foot of the hills, the French line occupied somewhat rising ground, in front of them was the rivulet of the Nebel running through low swampy ground, very difficult for the passage of troops.
Prince Maximilian commanded the French left, where the Bavarians were posted, Marshal Marsin the line on to Oberglau and the village itself, Marshal Tallard the main body thence to the Danube.
The French marshals, strong in the belief of the prowess of their troops, equal in number, greatly superior in artillery, and possessing an extremely strong position, scarcely paid sufficient attention to what would happen in the event of a defeat.

The infantry being posted very strongly in the three villages, which were very carefully entrenched and barricaded, insufficient attention was paid to the long line of communications between them, which was principally held by the numerous cavalry.

This was their weak point, for it was clear that if the allies should get across the rivulets and swamps and break through the cavalry line, the infantry would be separated and unable to reunite, and the strong force in Blenheim would run a risk of being surrounded without a possibility of retreat, as the Danube was unfordable.
Upon the side of the allies the troops were divided into two distinct armies.

That under Prince Eugene, consisting of eighteen battalions of infantry and seventy-four squadrons of horse, was to attack the French left.