Query: Approximately how many French troops were kept in Iberia during the Peninsular War?
Context: The vicious guerrilla fighting in Spain, largely absent from the French campaigns in Central Europe, severely disrupted the French lines of supply and communication. Although France maintained roughly 300,000 troops in Iberia during the Peninsular War, the vast majority were tied down to garrison duty and to intelligence operations. The French were never able to concentrate all of their forces effectively, prolonging the war until events elsewhere in Europe finally turned the tide in favor of the Allies.