Turn Your Eyes to the Trees: A timeline of Sardinia

For most of the Middle Ages, the island of Sardinia, in the western Mediterranean, was ruled by four indigenous Giudicato or Judgeships: Gallura, in the northeast, Logudaro, in the northwest, Cagliari, in the south, and Arborea, in the west. However, as the High Middle Ages passed, each giudicato fell, one by one, until only Arborea remained. Under Judge Marianus IV (The Great), Arborean armies swept the island, freeing it from the Aragonese who had occupied it. Marianus then proceeded to liberalize Arborea, making it one of the most progressive and developed societies in medieval Europe. He reformed army tactics, gave women the right to own property and divorce, and codified Arborea's laws, putting an end to the centuries of purely oral law. He died in 1375.

Fast forward thirty-two years. William III of Narbonne, Marianus' grand-nephew, is crowned Judge of Arborea in 1407. Just two year later, his army of 20,000 Sardinians would be defeated by Martin I of Sicily at the Battle of Sanluri, paving the way for the end of Arborea, and the conquest of Sardinia by the Aragonese king. But what if William III had won the battle?

Let us say that, rather than being divided as per OTL, the Arborean army remains in one piece, and manages to successfully defend the fortified town of Sanluri. Just a few days later, as per OTL, Martin dies of malaria, further demoralizing his army. Over the next year, William conducts a highly successful military campaign against the Catalan and Aragonese forces in Arborea, forcing them out by January 1411, and thus proving himself worthy as Giudice of Arborea. Martin II of Sicily takes the throne of Aragon that year, and is subsequently defeated by Arborean forces near William's territories at Bas. The ailing Martin is forced to concede the port of Valencia, and most of the coast of Aragon to Giudice William.

What would the effects be?

I'm intrigued. I wonder what would happen when Martin II dies. In OTL he had no heirs so there was a great conflict over who would inherit Aragon. His choice was James of Urgel, who was of a cadet line of the House of Barcelona. However the Trastamara of Castile put forth one of their own. The Angevins had a candidate as well. I would think that right away William might be more interested in the old Kingdom of Majorca (Rousillon, Montpellier + the Balearics) than Valencia. It would complement it would complement the Viscounty of Narbonne rather well.

As for long term affects I wonder what happens to Sicily. Does William go after it? I'm assuming that Louis III of Anjou successfully establishes himself in Naples without Aragonese interference. So after he succeeds Joan II does he go on to grab Sicily during the succession crisis in Aragon? A strong Angevin dynasty in southern Italy has huge ramifications. I would worry about Genoese interference in Sardinia though. They were major backs against Aragon but they will want something in return. Perhaps a break with Genoa could lead to the conquest of Corsica. That's a nice thought.

I would be answering your post in-depth, but unfortunately, I know next to nothing about the medieval Mediterranean. While the OP may make it seem that I know quite a bit, it's just that I know a lot about Arborea itself. So....li'l help?

That is interesting. I didn't know that Sardinia was unified in that manner.
Well, I think that most of Aragon's coast would not be ceded to Arborea. However, the Beleares and Amalfi and maybe other mediterranean islands could be ceded to Arborea.

Well to be honest it isn't exactly my area of expertise either. However I will give it a shot. At the time were talking about Sicily is ruled by a cadet branch of the House of Barcelona, the main line of which rules Aragon. (the original cadet line died out with Frederick III but Martin II's son Martin I maried his heiress Mary essentially starting a new cadet line). When John I of Aragon of the main line dies his younger brother Martin II of Sicily becomes King uniting Sicily and Aragon once more. The confusing thing here is that Martin II is the father of Martin I. He was also Martin I of Aragon (II of Sicily). Some sources just call him Martin the Elder. Also there are two Frederick IIIs because Frederick II specifically called himself Frederick III.

So anyways Martin I/II is the last of the House of Barcelona. When he dies there are several candidates. Yolande of Aragon was the senior female claimant as a daughter of Martin I/II's brother John I. She had married into the House of Anjou which ruled Provence and Anjou (a different branch under Joan II held Naples). However Martin I/II decided to appoint James Count of Urgel governor general in essence marking him as heir. James was senior claimant through the male line. Then there was Fadrique a bastard son of Martin I (so a grandson of Martin I/II) but he was of course illegitimate. Finally we have Ferdinand of Castile (House of Trastamara) younger son of the King of Castile and descended from Martin I/II's sister Eleanor. This was all sorted out by the Compromise of Caspe which gave Aragon to Ferdinand.

Now if Sardinia is independent under the House of Lara that upsets things a bit. First of all it puts a hostile power between Aragon and Sicily. Not only that but William and or his heirs, assuming he has some, have territories in neighboring France (Narbonne). I'm not sure if William would be strong enough to launch an attack on Aragon before the death of Martin. Would the people of Arborea support him? That's something you could answer better than I could. But the succession crisis presents an ideal time to intervene. I'm still not sure how much he could get. Given that Sardinia isn't really a huge power base. But at the very least he could definitively remove the Aragonese threat even if he doesn't make substantial territorial gains. It would also provide him some leeway to make a move against Corsica. The Genoese are coming out of a French occupation and facing threats from the Visconti of Milan so its an ideal time to go after Corsica. Indeed that's exactly what the Aragonese did OTL.

One other major affect would likely be in Naples and Sicily. At the time, in Naples, the reigning Queen was Joan II of a branch of the House of Anjou. She had no heirs. In OTL she adopted Alfonso V, son of Ferdinand I of Aragon, as her heir then had a falling out and adopted Louis III of Anjou (of the branch ruling in Provence and Anjou) who was a son of Yolande of Aragon. OTL Louis dies and Joan adopts his brother Rene but its all for naught as the Aragonese conquer Naples anyways. Naples goes to Alfonso's bastard son Ferdinand while Sicily and Aragon go to his brother John. This all happens in the 1420-30's.

So if Sardinia intervenes in the succession crisis and maybe takes the Balearics, Sicily and or Rousillon and possibly even puts a different candidate on the throne there's a lot that could happen. Even if they don't take Sicily themselves then Sicily is left open to the Angevin claimant. Possibly this could result in Naples and Sicily reunited but under an Angevin who also rules Provence. Alternatively they could take it themselves and we could have the Kingdom of Sardinia-Sicily with little bits of territory in mainland France/Aragon. This may not butterfly away Spanish unification (Aragon + Castile) later on but it would eliminate Aragon's Mediterranean empire and change or prevent the Italian Wars as we know them.

I kind of doubt that Sardinia could emerge as a great power but it could definitely act as a spoiler for Aragon and carve out a nice little powerbase for itself in the central Med. I don't know that much about Arborea (politics, government etc) to comment on what kind of regime it would be or how stable it would be. I suppose for a Sardinian empire to develop and control outlying territory William's line would have to be made heriditary Judges/Kings. Is this possible? This is probably where you can supply some more information.

Well, the Giudicato was already hereditary; William only came to the throne through a convoluted series of political marriages and alliances (much like most other European leaders). In OTL, the people of Sardinia were staunchly pro-independence. Though they did revolt against William later, this was only because of a perceived Aragonese claim to the Judgeship. Now, at the time, Arborea was one of the few nations in Europe to have a professional (though part-time) army, and a rather powerful one at that, as evidenced by the numbers William was able to raise against Martin I. If Arborea does stay independent, I believe (with what you've told me) that William would capture Corsica, turning on his Genoese allies. Then, during the succession crisis, he would certainly capitalize on the chaos; I'm not terribly sure which islands, Sicily, the Balearics, or what, he would invade, but that doesn't matter just yet. Basically, what I see is the emergence of Arborea as a major thalassocracy in the middle of the Mediterranean, wielding much economic influence in Italy. (Arborea had always been Italy-focused) Is this improbable?

That sounds entirely reasonable to me. I would watch how involved William gets in Aragon. The more I think about it taking Rousillon may be too much as it will drag him into Spanish conflicts too often. As it is his role as Viscount of Narbonne will likely involve him in French political infighting. I believe he sided with the Armagnacs. I get the sense that the Sardinians may not put up with too much foreign adventuring so maybe William will need to keep that to a minimum. Does Arborea have some kind of Charter governing the powers of the Giudice? Is it developing along the lines of a crowned Republic or is it more monarchical? And it seems that some of the earlier Giudice assumed the title of Rex Sardiniae. Does William take the title Rex Sardiniae (et Corsicae once he takes Corsica) after he expels the Aragonese or does he remain Giudice out of tradition or legal obligation?

I think an alliance with the Angevins may help. It may come at the cost of Sicily but if Sardinia gets some nice trade rights out of the deal then that's fine - gives you your economic influence. Plus you will need a strong power in Naples and Sicily to fend of the Ottomans in a few decades. From there you could do almost anything because the Italian wars will play out completely differently so Sardinia could end up with half of Italy or nothing depending on what happens.

One other note, William needs an heir. I'd love to see the traditional Narbonnaise name Aimery. It passed into Italian as Amerigo when one of his ancestors invaded Italy. The Sardu form of William is Guillermu, I'm guessing Sardu for Aimery would be Amerigu but that's a guess. Marianu would be another great name.

Well, Arborea was quite unique, in that while it gave its citizens substantial civil rights (even for today!), it gave them little-to-no involvement in the government. And yes, Arborea used the Carta de Logu implemented by giudicatessa Eleanor in 1392. Absolutely massive legal code, summed up really everything one could want to know about Arborea's legal policies.

The Sardinians would probably welcome a "native' Rex Sardiniae; however, he would have to make some major changes to the Carta. The title "Judge of Arborea" is quite different from the title "King of Sardinia". I believe that he would likely not take the title of Rex Sardiniae, and simply remain the Giudicato de Arborea (and late, Giudicato de Arborea et Corsica). I imagine that the name "Sardinia" would eventually pass out of use in favor of the name "Arborea".

All right. I think we have a coherent basic situation set up; I'll start writing the TL tomorrow, and I hope to have the first li'l episode by 3:00.