The Mérida Offensive was a military operation carried out by the Nationalists during the very early phase of the Spanish Civil War in August 1936; it formed part of the Extremadura campaign. Its primary objective was connecting two rebel zones, separated by the loyalist-held southern Extremadura. The operation was designed and prepared by Franco; its starting point was Seville. The raid was executed by an improvised force, which grew from 1,000 at the beginning to 5,000 later, and was mostly composed of the Foreign Legion and the Regulares infantry units. Most of the time the Nationalists operated in two battlegroups usually referred to as "columns", commanded by Asensio and Castejón. Between August 2 and August 11 they performed a breakthrough raid of some 180 km, defeating much more numerous yet loose and poorly organized loyalists during engagements at Santa Olalla, Monesterio, Llerena, Los Santos de Maimona, and Almendralejo; the operation climaxed in the battle of Mérida. The success of the Mérida Offensive linked two rebel-held zones and proved of paramount importance for future military developments in 1936; it was also vital for the future rise of Franco as overall rebel commander.
Preparations
First steps
On July 24, five days after his arrival from Canary Islands to Tetuán, Francisco Franco sent one of his chief aides, colonel Francisco Martín Moreno, by plane from Morocco to Seville. The objective was to start organizing troops for a planned advance north. At the time there were some 400 km in a straight line across loyalist-controlled territory from Seville to Madrid; the closest point controlled by the rebels in the north was in the province of Cáceres, some 160 km across the loyalist zone from the rebel enclave in Andalusia. On the very same day the Burgos-based rebel military executive, Junta de Defensa Nacional, nominated Franco "Jefe del Ejército de Marruecos y del Sur de España".
The nomination made Franco commander of rebel troops in Morocco and in the southern peninsular enclave. They were firmly established in the area around Seville and Cádiz, with shaky connection to Córdoba. Numerous smaller locations in both provinces were controlled by the loyalists, though they formed separate islands of resistance and were pressed by the insurgents. The latter were also advancing west, towards another provincial capital, Huelva, in hands of the government. In total, the rebels had some 6,000 rebel troops in the southern enclave, though these were mostly inexperienced recruits in garrisons taken over by conspiring officers. Until July 24 no more than 500-600 battle-worthy soldiers have been transported from Africa across the Straits, some 400 by a unique naval convoy which managed to make it through the governmental blockade, and few hundred lifted by air since July 19. The airlift continued, albeit at a very slow rate, below 100 men daily.
It is not clear whether the Ministry of War in Madrid had any plan of action for the southern part of the country. At the time its key initiative was an offensive against the rebel-held Albacete. None of the sources consulted provides information whether the government was taking into account a would-be rebel offensive from western Andalusia towards Extremadura. However, on July 25 the minister of war general Luis Castelló nominated coronel Ildefonso Puigdengolas, an experienced officer who had just suffocated rebel islands of resistance in Alcalá de Henares and Guadalajara, the military commander of Badajoz. Puigdengolas flew from Madrid to Badajoz the same day and assumed command in all loyalist-held Extremadura. He immediately started to form organized combat detachments from forces of order, militiamen and what remained of infantry sub-units. How many people he had under his command is not known; intendancy figures for Badajoz-based militia only were up to 5,000; together with militiamen from smaller locations and the forces of order, the figure was probably much higher. Though the usual railway connection with Madrid via rebel-held Cáceres was broken, southern Extremadura was linked with the capital by a railway line via Ciudad Real.
On July 28 key rebel commanders in the south met in Seville; the Andalusian commander general Gonzalo Queipo de Llano played the host, Franco and general Luis Orgaz flew in the day before from Tetuán, and general José Varela arrived from Cádiz. Exact content of the meeting is not known, yet historians speculate that it was dedicated mostly to sorting out problems of command, priorities and resources. Reportedly there was some tension about usage of the troops which were being shifted from Africa. Franco, since July 24 the superior of Queipo, was allegedly "furious" about his men being deployed by the latter against local pockets of resistance; Franco claimed that attrition rate suffered when achieving what he considered a secondary objective might prevent an efficient thrust north.
Final touches
During the last 5 days of July loose rebel detachments, unrelated to troops shifted from Africa, were outflanking from both sides the major road leading from Seville towards Extremadura; in northern Andalusia it was controlled by the loyalist militias. On July 27–28 so-called Columna Carranza, led by a local Seville Falangist, took control of Guillena (18 km from Seville, 4,500 inhabitants), and Burguillos (22 km, 1,500 inhabitants), two towns east of the main road to Cáceres. Slightly later, on July 29–31, a detachment led by a Guardia Civil NCO Juan Ruiz Calderón took over locations west of the road, namely Gerena (22 km, 4,500 inhabitants), Las Pajanosas (23 km, 1,100 inhabitants), and El Garrobo (31 km, 800 inhabitants). In all these cases combat registered, if any, was minor skirmishes and loose shootout. On July 29 Franco radioed Mola that "se consolida la situación Andalucía" and new troops were being airlifted every day, but said nothing about any offensive north. This was also the day the first German transport plane arrived in Morocco; other German and Italian aircraft would be arriving during the next 10 days, increasingly the airlift capacity. From July 19 until the end of the month some 850 men from the Army of Africa have been airlifted at a rate of some 65 per day, yet with August commencing rebel commanders believed (overoptimistically, as it would turn out) that they now reached the daily airlift capacity of 500.
On August 1 Franco issued from Tetuán his Orden General de Operaciones n.º 1 del Ejército de África y del Sur de España. He ordered the troops shifted from Africa to Andalusia to commence a general advance north the following day. The objectives were specified as the cities of Zafra (120 km away) and Mérida (170 km), though no specific date for their capture has been set. Once there, troops should be prepared for further advance, either/or towards Cáceres (230 km) and possibly Badajoz (190 km). The priority was not consolidation and systematic control, but speed: "la característica del avance ha de ser la rapidez, la decisión y la energía evitando toda detención no imprescindible". Formation of another breakthrough unit, to follow suit, was also anticipated. Suffocating local focos of resistance in Andalusia was declared a secondary objective. On the very same day Franco radioed Mola that he intended to deliver north 2m cartridges, badly needed by Mola's troops, either via Cáceres or, as option B, via Portugal (Huelva was seized by the rebels on July 27, and hence they reached the friendly Portuguese frontier). In his radiogram Franco confirmed that his offensive would begin on August 2.
On August 2 Franco flew for the second time from Morocco to Seville. They key reason was to supervise personally the formation and departure of the task force, entrusted with the breakthrough raid to Zafra and Mérida; he "aimed at seeing his first column off". Another reason was again discussing with (according to some authors protesting to) Queipo the division of resources and preventing intensive use of African troops to suffocate local islands of resistance; Franco continued to believe that his troops were taking too much casualties, which impaired their potential when marching towards Madrid.
The Raid
August 2 (departure)
During most of the day troops supposed to commence the offensive towards Extremadura were being assembled, organized, supplied and re-armed in Seville. In the afternoon, this improvised battlegroup, named Agrupación n.º 1, left northbound along the main road leading to Mérida. Its commander was teniente coronel Carlos Asensio, a 40-year-old officer experienced during the war in Morocco in the 1920s; since early 1936 he has been commanding indigenous Moroccan troops, the regulares. The key component of this improvised battlegroup was IV. Bandera del Tercio, a battalion-size unit of the Foreign Legion; another one was II. Tabor de Regulares de Tetuán, also a battalion-type, but much less numerous and worse equipped unit of the Moroccan infantry. Both units had been previously transported from Africa. They were supported by one field battery of 70 mm guns (unclear whether ferried from Africa or originating from one of Andalusian garrisons), a machine-gun sub-unit, pioneers and non-combat services.
Given standards of the Spanish army of the time, these units in total would have normally amounted to some 1,000 men, and it is the figure provided by some historians as strength of Asensio's men, though others might point even to 2,500. The battlegroup, in Franco's radiograms soon to be called "columna" (a name also widely accepted by historians), departed in a huge motorcade of buses, trucks, passenger cars, motorcycles, tankers, tractors and other specialized vehicles. The column spread over the distance of few kilometers, and drove very slowly northwards for some 30 km, to the neighborhood of the small town of El Garrobo, the last settlement in hands of the insurgents. Afterwards, already after sunset, they left the rebel-controlled area and proceeded towards the unknown.
August 3 (Santa Olalla)
Around 1 AM the vanguard detachments stopped before Rivera de Huelva; a bridge over this rather small river had been blown up by the militias from the nearby loyalist-held town, El Ronquillo, unclear whether shortly before the rebel arrival or earlier. Though fording was no problem for infantry, vehicles were not in position to cross. As there was no close alternative bridge available, the column stopped.
Asensio ordered few platoons of regulares to move forward on foot; they made some 6 km before reaching El Ronquillo (40 km from Seville, 2,000 inhabitants). Following a brief night shootout and taking 1 WIA as casualty, the Moroccans seized the city. It took 12 hours to repair the bridge, and the column moved forward, only to find the next bridge destroyed as well. Attempts to find a detour resulted in 4 trucks and 1 tanker broken; repair took other 6 hours. The entire column reached El Ronquillo around 6 PM.
Having appointed local authorities during the evening, Asensio, with vanguard sub-units, left El Ronquillo and moved north. This time there were no problems and having covered some 20 km around 10:30 PM he reached Santa Olalla, (60 km, 3,500 inhabitants), which he entered with no combat. On August 3, Asensio made some 27 kilometers. He was unaware that at the time in Monesterio, a larger city some 20 km further north, 20 truckloads of militiamen left to confront him in Santa Olalla, to reach the town during the forthcoming night.
While the bulk of Asensio's column was in El Ronquillo, in late afternoon another similar battlegroup was leaving Seville. Named Agrupación n.º 2, it was led by comandante Antonio Castejón; like Asensio, he was also an experienced 40-year-old officer, though with the Foreign Legion, not the Moroccans. Key components of his battlegroup were two battalions, V. Bandera of the Legion and II. Tabor de Regulares de Ceuta. It included also some armored vehicles of Guardia de Asalto, few artillery pieces in an improvised unit, plus pioneer, medical and logistics services. The column also moved in some 100 vehicles; as the night fell they drove at a snail's pace along the main road, the section taken by Asensio 24 hours earlier, and would not reach El Ronquillo before dawn of the next day.
Sometime during the day Franco radio-wired Mola that his troops had just started the advance north. He either was optimistic or pretended to be so, as he claimed he remained in good relations with Berlin and Rome, that he expected the aircraft issue to be sorted out soon, and that he anticipated successful drive towards Madrid to be completed soon ("llevar a cabo acción intensa sobre Madrid").
August 4 (Monesterio)
Very early, trucks with militiamen from Monesterio arrived at the northern outskirts of Santa Olalla, where they were fired at by vanguard patrols of the Asensio's column. Skirmishes turned into a full-scale engagement, the first one of this sort. The night exchange of fire lasted few hours and ended in total dispersion of the militia group. At the battlefield they left 14 KIA and the rest returned in disarray to Monesterio; Asensio recorded a few WIA.