Throughout the 19th century, the population of the town doubled from the 10,000 inhabitants at the beginning of the century to around 21,000 by the beginning of the 20th century. During this period, Albacete defended Queen Isabel II against the Carlists (the supporters of Charles, the pretender to the Spanish throne), supported Espartero and, just like other Spanish cities, constituted a revolutionary junta. During the long period of the Restoration (1875–1923), symptoms of "caciquismo" (the network of social relations based on clientelism underpinning the political life in the rural areas) became pervasive in the political and social life of Albacete.