The year is 1807. Hundreds of years ago, with no explanation whatsoever, Magic and its practice disappeared altogether from England, the only place in the world where it was found. Before this time, Magic was deeply rooted into English history, nature and land and gave rise to the English national character. However, within the past few years, Magic has returned to England through the independent efforts of the seasoned scholar Gilbert Norrell and the young and brash Jonathan Strange. Both are land-owning aristocrats. Norrell has been studying Magic for decades and hoards most of the useful books of Magic in England for himself, and it is only by becoming his pupil that Strange is able to develop his ability.
War rages across the European Continent as Britain stands alone against the Napoleonic Menace. The British Government asks Jonathan Strange to accompany a large detachment of the British Army as it lands in Iberia to support Spanish and Portuguese resistance against the French occupation, and support Britain's war effort through magical means.