In fact, the Vittoria campaign illustrates the immense advantages gained by a leader, who is sure of his rear and of one flank, over an enemy who is ever nervous about his communications.

The British squadron acted like a covering force on the north to Wellington: it fed the guerilla warfare in Biscay, and menaced Joseph with real though invisible dangers.

This explains, in large measure, why our commander moved forward so rapidly, and pushed forward his left wing with such persistent daring.

Mountain fastnesses and roaring torrents stayed not the advance of his light troops on that side.

Near the sources of the Ebro, the French again felt their communications with France threatened, and falling back from the main stream, up the defile carved out by a tributary, the Zadora, they halted wearily in the basin of Vittoria.
There Joseph and Jourdan determined to fight.