I'm working in a TL with this "What If", but it's in spanish and at the moment I don't want to translate it.
It is possible to start a thread in spanish?
My POD is at the very first moment of the revolt in Melilla; the change butterflies general Queipo de Llano controlling in the city of Seville on July 18th because weapons are given to the unionists. The example of unionists fighting in Sevilla provoque the appointment of Largo Caballero as the new premier that same day, after the demision of premier Quiroga (instead of Manuel Barrios or José Giral). The new government is mainly socialist but with ministers of every party of the Popular Front, and the first decisions are slightly different: on July 19th's morning weapons are given to the unionist and members of PF parties and they start forming columns; the army is not disbanded but reorganised in a new Loyal Army that includes all the Guardia Civil and Guardia de Asalto that support the republic; the colectivization of lands and factories are recognised by the governement early in TTL, etc.
If the Republic prevents Franco from getting to Africa, the war could also be much easier for the Republic.
Exactly: The point in TTL is that without the airbase of Sevilla or Granada, the airbridge between northafrica and Spain is less efficient and even if the nationalists control Cadiz, Algeciras and Cordoba, they never get out of Andalucia and never unite with the troops of General Mola in the north.
If Britain and France will help them win, then the Soviets will never gain as much influence as our TL
Even if socialist France is willing to help Spain, Britain is not and Leon Bloom will obey his ally because France needs it.
In orther to change british attitude towars the conflict my idea is to change the "Convoy of Victory" event and provoque a conflic when nationalist gunboat Dato hits HMS Basilisk in Gibraltar after misidentifying it as republican. After this Britain allow France to give to Spain the weapons that were already bought at the beggining of the war. Also the discovery of Italian airplanes in french northafrica and german airplanes in the Usaramo going to nationalist Spain create another international conflict and at the end Germany and Italy stop supporting Franco.
Likewise, if they win quickly because the Nationalists screw up worse at the beginning, or the uprising is crushed in more places, the Soviets won't have too much influence.
Not much soviet influence; but in this scenario, after maybe 6 or 9 months of war, the influence will be on the side of the anarchist CNT. The socialist party in Spain will divide between the prounionists and the antiunionists. The soviets will support the moderate wing of the socialist, maybe entering the party. President Azaña will force the demision of Largo Caballero, ending the Popular Front and calling for new elections hoping to retake power for his liberal party because many right parties are illegal. If the anarquist and left-socialist unite, they will keep many of the economic reforms they have impose during war. So you may have a liberal Republic of Spain with workers self-management in half the industry and almost all the agriculture, but still capitalist (like a strange mix of Yugoslavia and Sweden?) and almost stable by 1938.
Would the Republic Declare War on the Axis as revenge for Germany and Italy supporting Franco?
Not in this scenario. There will be anarquist volunteers in France, because they hate nazis and fascists, but the government know their military is weak... this Spain will try to modernize their industry and increase its standars of living, so maybe they will even trade with Germany (germans need tungsten). Specially if this leftist Spain is boicoted by Britain after some nationalizations (like Mexico did with their oil...).
Germany overruns Spain in 1940 after conquering France. It is liberated in 1944 at the same time as Operarion Dragoon.
Infante Juan is installed as King of Spain to minimize communist influence.
Ok to the first part, but if Spain trade with them (like socialist Sweden did) they might wait. Maybe Italy could be more interested in controlling the Balearic Islands in order to counter the british in Malta during the Greece invasion.
Anyways, no communist influence in Spain means nobody imposes a King... after all anarquists are very anti-communists, or at least very anti-soviet-russia. And Spain is capitalist, self-managed by workers, but capitalist.
Mexico backed the Republic as well, but Mexico wasn't exactly a great power
The main change would be in Latin America. Many authoritarian states in the region had looked to Francoist Spain as a model for how to run society without having the Left (broadly defined) as a major force, and for a brief period (by only looking surface-deep) it seemed like Spain under Franco (and, for that matter, Portugal under Salazar) managed to become successful. Without a successful model of a right-wing authoritarian state lingering on past WW2, it would be difficult to see authoritarianism surviving past WW2. If conflict does emerge, than most of Latin America would look like Colombia during this period rather than the stereotypical military dictatorships.
I can imagine an intense interaction between this Spain and Mexico at first, because of the backing during the war. If the spanish model of self-management has some succes (from 1937 to... lets say 1941, the have some years to show a tendency) this model may spread when the spanish population scapes from Spain during WW2 and go to Hispanic America. Imagine Peron implementing some ideas in Argentina or Lazaro Cardenas in Mexico.
Maybe is too much but... what if in this scenario Henry A Wallace during his 1943's tour in Latin America is someway influenced by those examples and became more critic towards the soviets? Maybe he repeats as vicepresident and became president in 1945.
A very different second half for the XX century, that's for sure.