For most British readers, the Peninsular War is synonymous with the campaigns of Sir John Moore and the duke of Wellington. That this should be the case is hardly surprising in view of the fascination which they have exercised for many historians at the expense of other aspects of the struggle. In defence of such anglocentrism, it might be argued that British involvement was the decisive factor in the war and, further, that without the duke of Wellington the Iberian Peninsula would never have been freed from French domination. That is true enough, but it is also true that Wellington could never have been successful but for the continued resistance of the Spaniards and the Portuguese. Indeed, it is fair to say that without the thousands of Portuguese soldiers who served in his army, and the indirect assistance provided by the Spaniards in pinning down a large proportion of the French forces, the Duke was so outnumbered that he could never have carried the war into Spain at all. Given that Wellington could probably have maintained a British presence in Portugal almost indefinitely, the Spanish contribution is of particular importance. While the British were still bottled up in Portugal during 1810 and 1811, however, the French all but destroyed the basis for Spanish resistance. Had not the Russian campaign intervened to divert Napoleon's attention eastwards, and with it the vital reinforcements that might have completed the French conquest, Spain could conceivably have been subdued. Wellington's victories of 1812 and 1813 would then have been an impossibility.
New Lights on the Peninsular War: International Congress on the Iberian Peninsula, Selected Papers, 1780-1840
