Strategic Geography and the Spanish Habsburg Monarchy's Failure to Recover Portugal, 1640-1668

In a war lasting almost twenty-eight years (1640–68), Spanish forces endeavoured to recover Portugal for the Spanish Habsburg monarchy. This article examines the war in terms of strategic geography, a crucial but rather neglected dimension of early modern military history. Drawing comparisons with Alba's successful 1580 campaign to annex Portugal, it shows how geographic and climatic factors influenced the conduct of the 1640–68 war in terms of strategy, tactics, and logistics. It also reveals how these factors contributed to the outcome of the war and to Spain's military failure against its smaller neighbour.