 In January 1810 , the city of Cádiz , a major Allied harbour and the effective seat of Spanish government since the occupation of Madrid , was besieged by French troops of Marshal Soult 's I Corps under the command of Marshal Victor . The city 's garrison initially comprised only four battalions of volunteers and recruits , but the Duke of Alburquerque ignored orders from the Spanish Junta and instead of attacking Victor 's superior force , he brought his 10 @,@ 000 men to reinforce the city . This allowed the city 's defences to be fully manned . 
