Sir John Fortescue holds a pre-eminent place amongst British military historians, his enduring fame and legacy resting mainly on his life's work "The History of the British Army", issued in 20 volumes, which took him some 30 years to complete. In scope and breadth it is such that no modern scholar has attempted to cover such a large and diverse subject in its entirety; but Sir John did so and with aplomb, leading to a readable and comprehensive study. According to Professor of Military History Brian Bond, the work was "the product of indefatigable research in original documents, a determination to present a clear, accurate, and readable narrative of military operations, and a close personal knowledge of the battlefields, which enabled him to elucidate his account with excellent maps. Most important, however, was his motivation: namely, a lifelong affection for the old, long-service, pre-Cardwell army, the spirit of the regiments of which it largely consisted, and the value of its traditions to the nation. An important part of his task was to distil and inculcate these soldierly virtues which, in his conservative view, contrasted sharply with the unedifying character of politicians who habitually meddled in military matters." ODNB. This seventh volume covers the period from 1809-1810, after a disastrous raid into French held Holland, the British government decided to use all their power to the strike at Napoleon at his weakest point, Portugal and Spain. After the British foray into Spain in 1809 culminating the bloody victory at Talavera, the British troops retreated into Portugal before the overwhelming French numbers. Inflicting a punishing check to the French invasion force under Mass?na at Bussaco, the British army marched to the massive and impenetrable lines of Torres Vedras close to Lisbon.