Foch had previously been based at Doullens north of Amiens .
Foch had previously been removed his headquarters to Cassel to take advantage of its strategic position near the northern end of the Western Front and to be closer to the Belgian headquarters at Veurne .
Foch had previously been based at Doullens north of Amiens , but removed his headquarters to Cassel to take advantage of its strategic position near the northern end of the Western Front and to be closer to the Belgian headquarters at Veurne .