[12] In 1895[13] Marco Pérez married Bruna Ilincheta[14] Zalba (1869–1931), a girl from Navascués, a town in the neighboring Salazar Valley;[15] she was daughter to a local merchant.

He was skeptical about the secular nature of the original draft statute but backed its version amended during the rally of Navarrese alcaldes in Estella;[50] in the Carlist press mouthpiece El Pensamiento Navarro[51] he mobilized support from local town halls.

[52] In late 1931 Marco grew increasingly suspicious of the left-wing course adopted by the Diputación;[53] in particular, he was enraged by its decision not to support financially the construction of a new seminary in Pamplona.

Until the outbreak of the Civil War Marco remained a local politician active in-between the county and the provincial level; his only episode related to national politics was the 1935 engagement in the buildup of Bloque de Derechas, a Navarrese coalition co-engineered by the Carlists with the right-wing minister of justice Rafael Aizpún.

Then he formed part of the command layer of Tercio Nuestra Señora de Camino,[64] a battalion deployed first on the Northern Front, then in Teruel, and finally in Levante.

[71] The Navarrese Carlist executive was increasingly fragmented and split between 3 competing groups; the party nationwide leader Fal Conde appointed him to a 3-member task force entrusted with working out a solution.

[75] Moreover, following the outbreak of the Nazi-Soviet war he approached the German consulate in Pamplona and offered requeté support, the move immediately disauthorized by the Navarrese jefé Joaquín Baleztena.

[77] Marco was fully compliant with unification of Carlism into the Francoist state party; when in 1941 Serrano Suñer decorated him with military awards he appeared in full FET gear, causing indignation of mainstream Carlists.

[78] In 1942 and in alignment with Arrese he advocated that Traditionalists adopt a collaborative stand and take seats in the Pamplona ayuntamiento; the new Navarrese party leader Jesús Elizalde considered it disloyal and suggested some disciplinary measures.

[79] When later in 1942 Marco was nominated secretario provincial of FET[80] and then got appointed to the III Falangist Consejo Nacional,[81] ranked #60 on the list of nominees,[82] he did not seek approval of the Carlist executive.

[87] Also in 1943 Marco declared support for Karl Pius Habsburg, styled as the Traditionalist claimant Carlos VIII; the pretender led the breakaway Carlist faction of carloctavistas and with the permission of the regime, started to tour to country.

[95] Initially his relation with the 1945-appointed civil governor Juan Junquera was excellent; both toured Navarre and Marco contributed with his expert knowledge about people and places.

[101] At the turn of the decades Marco made a U-turn and was seeking alliance of other Carlist currents against the new civil governor, Luis Valero; in 1950 he demanded re-opening of javierista círculos,[102] though he might not have been entirely good-willed.

[119] At the time he got detached from carloctavismo, as the claimant unexpectedly passed away and the movement disintegrated into almost non-existence; Marco represented rather sort of generic Francoism embodied in the strong, Navarre-attached personality, by enemies referred to as "eterno cacique navarrista".

According to some authors, Marco took advantage of his position in Diputación and generously assisted some of these private entities with public money, e.g. by granting tax exemptions, donating communal property and straightforward financial aid; by some he is considered a typical example of the corrupted “fauna franquista”,[136] though other scholars claim that during his public service Marco retained total integrity, did not enrich himself either duly or unduly, and lived Spartan life which would later border poverty.

As a provisional measure until the end of the term Marco, who was the oldest member of the chamber, was appointed its acting vice-president;[142] according to some scholars at this point "sector tradicionalista" regained control over the body and started to reverse some of the changes instituted earlier.

[147] As a vascophile he supported the setup of Patronato de Fomento del Vascuense and became its president,[148] a follow-up of his earlier co-initiative of setting up Basque ikastolas[149] and other initiatives.

[152] He also spoke against Pamplona strikes following the MATESA scandal, in careful wording denouncing disturbances which reportedly posed a threat to labor conditions and the local economy.

[163] In early 1977 Marco was among co-founders of Alianza Foral Navarra,[164] a right-wing party focused on Navarrese identity by some scholars categorized as the post-Francoist “bunker”,[165] and became its president.

[166] The organisation demanded restoration of traditional Navarrese establishments and sponsored similar declarations of the Diputación,[167] against a competitive project favored by UCD;[168] during general elections AFN garnered 8,5% of the votes in Navarre and was the 4th political force in the province.

[169] In 1977 AFN and Marco personally turned most vehement opponents of the plan to merge Navarre and Vascongadas into one autonomous community, already discussed between the Madrid government and the Basque politicians.

ETA planned 2 attempts against Marco, numerous acts of progressist[170] and Nationalist[171] violence against AFN followed, and the left-wing press staged a vehement propaganda onslaught; they counted him among “notorios fascistas”[172] and charged him with using Diputación for sectarian party purposes.

[173] The anti-merger campaign climaxed in a grand rally in Pamplona in December 1977; Marco emerged among the key speakers and lambasted the would-be merger as "suicide" of Navarre.

[179] In this capacity he led the talks with central authorities on the exact shape of the Navarrese regime and demonstrated an intransigent stand, focused on restoration of the 19th-century Ley Paccionada.

[181] Eventually Marco was offered minor concessions which allowed his “honrosa capitulación” and which opened the path towards Real Decreto Paccionado of January 26, 1979;[182] also in 1979 he signed the agreement on the Navarrese electoral regime[183] and numerous other arrangements.

The progressist and Basque nationalist authors present him as a local Francoist boss who during an exceptionally long tenure[195] developed his own clientelistic network and hugely contributed to the buildup and tight grip of the regime in the region.

[198] His anti-democratic outlook is undisputable; some categorize him as “a fascist”[199] and also the right-wing authors agree that in the late 1970s he considered the ongoing change a temporary shift and anticipated that democratization would turn into an episode.

[200] At times he appears in present-day political debates as a point of reference, standing for a sectarian right-wing fanaticism;[201] he is denied Basque credentials and ridiculed as a false vascophile.

According to this reading, Marco confronted the centralizing Francoist regime and tried to find a “third way”;[204] later he provided a crucial contribution when preventing the takeover of Navarre by the militant Basque nationalism.

[208] Charges of financial misdeeds are rejected by authors who note that Marco spent his last years bordering destitution in an old, dilapidating family house in Navascués.