[5] Following the Carlist defeat he had to abandon his job and settled in Cañete, a village on the western slopes of Montes Universales, a southern ridge of Sistema Ibérico.

[9] Some time in the mid-1850s Domingo Polo developed very serious health problems and pledged that in case of recovery he would dedicate his life to God; indeed he later entered an unspecified religious order and became a friar.

[25] Except that it was a collection of short stories[26] instead of a novel, it revealed characteristics marking his later works: traditional themes, a simple plot and clear educational purpose, with narration set in the provincial milieu of Sierra de Albarracín, painted with attention to detail and with a focus on local customs typical rather of an ethnographical study.

[27] All these features were developed in Polo's first novel, Los Mayos (1878),[28] a rural love story intended as a praise of loyalty and fidelity[29] and considered his best work,[30] translated into Italian and German.

[35] The last of Polo's major literary works, El guerrillero (1906),[36] revealed more threads of an adventure story; set during Third Carlist War, it was heavily based on wartime recollections of his brother Florentino.

[38] Among his contemporaries Polo was appreciated usually by those sharing a similar traditional outlook, such as Emilia Pardo Bazán[39] and his friends Marcelinó Menéndez y Pelayo[40] and José María de Pereda.

[46] By favourably disposed contemporaries he was put next to Fernán Caballero, de Pereda, Francisco Navarro Villoslada, Julio Alarcón y Meléndez, Juan Valera and padre Coloma;[47] critics dubbed him a "mamarracho literario" (literary monstrosity.

[69] He did not develop any original philosophical contribution himself; apart from works on history and general overviews, Polo is known for confronting some trends forming the liberal educational mindset, especially Krausism and Darwinism.

[72] During the last decades of the 19th century, Krausism became a philosophical powerhouse of liberal Spanish politics, represented mostly by Francisco Giner del Rios and Instituto Libre de Enseñanza.

[74] His friend Polo remained rather a proponent and did not construct his own anti-Krausian theory, though his vehemence gained him the description of "grande enemigo de la barbarie krausista" (great enemy of Krausist barbarism),[75] especially as Spanish Krausism, initially avoiding direct confrontation with the Church, later assumed a decisively challenging tone.

Some view it as an exemplary obscurantist Catholic reaction to scientific progress,[80] dismissed as "involucionismo, integrismo, tradicionalismo e ideario reaccionario" (involutionism, fundamentalism, traditionalism and reactionary ideology.

[83] Though his stance on Darwinism is portrayed as "aggressive and intolerant attack",[84] others consider it in line with scientific standards of the era, systematic and posing questions - like those related to hereditary transmission or variability patterns – which remained unanswered until the 1920s.

[85] A detailed study suggests that Polo engaged in the discourse not so much to challenge evolutionary theory,[86] but to confront secularism which used it as a ram against the Spanish Catholic outlook.

[103] In the upper chamber he continued to defend the position of the Catholic Church,[104] especially during the Ley del Candado crisis;[105] he was somewhat acknowledged as a dangerous opponent by procedural gimmicks employed by his adversaries.

[111] Revealing interest in the emerging workers’ question[112] he contributed to Acta de Loredan,[113] published the official Carlist program[114] and persuaded the claimant to re-organise the party, uniting the military and civil command chain.

[122] Also on the national scene, bedeviled by intrigues among Carlist pundits, Polo's relations deteriorated, including those with Carlos VII and especially his wife Berthe de Rohan.

[123] He considered his resignation handed to the new Carlist king Jaime III a purely procedural gesture, and was shocked to see it accepted,[124] though as a senator he was appointed to national executive, Junta Nacional Tradicionalista, in 1912.