At the siege of Burgos, from 19 September to 21 October 1812, the Anglo-Portuguese Army led by General Arthur Wellesley, Marquess of Wellington tried to capture the castle of Burgos from its French garrison under the command of General of Brigade Jean-Louis Dubreton. The French repulsed every attempt to seize the fortress, resulting in Wellington's withdrawal. The siege took place during the Peninsular War, part of the Napoleonic Wars. Burgos is located about 210 kilometres (130 mi) north of Madrid.

The Anglo-Portuguese Army was the combined British and Portuguese army that participated in the Peninsular War, under the command of Arthur Wellesley. The Army is also referred to as the British-Portuguese Army and, in Portuguese, as the Exército Anglo-Luso or the Exército Anglo-Português.