While I know that they converted to Catholicism at the Third Council of Toledo and ran a healthy slaving economy, everything else is quite vague.
I don't really know about slavery or what importance it had in this period, but I'm sure the economy had already switched to feudal based as in other places of Europe.
Therefore, without the Arab conquests, how would the kingdom develop? Would it eventually get challenged by the Franks or would it collapse in on itself?
When this issue has come other times I've been skeptical about the Franks making many inroads. It says something when sources coincide in that the Franks are
more hated than the Goths by the Romanized population - in what would become Catalonia and the Gallo-Mediterranean coast at least. On the other hand, some have pointed that the situation in 711 after Guadalete wasn't that different from that in 507 after Vouillé, and that given a different course of events the kingdom could have already collapsed in the early 6th century, so who knows.
I am curious what language was spoken at the time of the muslim conquest. What percentage of the population still spoke Visigothic, versus Roman, versus pre-Roman languages? It is natural to assume that a continued Visgothic Spain would develop along the lines of Frankish Gaul and eventually have a Romance language be the common tongue, but is that necessarily the case?
Gothic was rare to begin with, and pretty much every author says that it was either dead or dying by the time of the Muslim conquest. The vast majority of the population was Romance speaking, as it was during the times of the Emirate in fact. (Proto/Old/Whatever) Basque was more widespread, but the more Romanized population in the lowlands and the Ebro basin was probably already bilingual. I have no sources to back this, but I'd imagine that Gothic took the definitive peg down when Reccared dismantled the Arian church already in the late 6th century.
Linguistically, "Spanish" would be much more like Catalonian without Arab influence.
Catalan is a Gallo-Romance language whose origin dates back to the Frankish conquest of the Spanish March. All other Iberian languages are Ibero-Romance. The thing is that, when you read texts in Old Galaic-Portuguese, Astur-Leonese, Old Castilian and Aragonese, they aren't really that different from each other. The language that would have existed in a late-Medieval Visigothic kingdom would resemble these. Obviously, without tangible Arabic or Basque influence (which is the case in Castilian).
In "The World of Late Antiquity," Peter Brown claims that the word for "executioner" (verdugo) is the only Visigothic loan word to survive in Spanish. Interesting if true...
Guerra, yelmo, espuela, guardia, dardo, espía... there are a few more. It's true that all of them are related to war and violence in one way or another, though...
Indeed, the Visigoths were concentrated here and there
Quote:
For much of their history in Spain, the Visigoths kept themselves apart from the native Hispano-Roman population. The Visigoths always were a small minority, accounting for less than 12% of their kingdom's estimated population of 10 million. Visigothic settlement was concentrated along the
Garonne River between
Bordeaux and
Toulouse in
Aquitaine, and later in Spain and Portugal around the
Ebro River, around the city of Mérida, between the upper reaches of the
Douro River, in
Tierra de Campos also known as
Campi Gothorum in Central
Castile and León, Asturias and
Toledo, and along the
Tagus River north of
Lisbon. Little Visigothic settlement occurred elsewhere in the kingdom
As for political stability I am not sure of that. They were prone to civil wars and revolts.
What's the source of this? I'm pretty sure that the numbers are wrong. Spain had 10 million people in the 19th century. The numbers I've most often seen for the late Roman period-early Middle Ages are or 4 million people in the Iberian Peninsula. The Goths are estimated as a maximum of 200,000 upon arriving, but probably closer to 100,000 or even less. The Suebi nobility was later absorved into the Gothic but they would have been even less for obvious reasons.
The vulgar Latin of Castille and Andalucia retained much more Moz-Arabic (Vulgar Latin written with Arabic Script) than did the areas of the two lateral coasts of Iberia, which is evident by Portuguese's closer grammatical and phonetic ties with Catalan, and Gallo-Romance languages as a whole.
Portuguese is way closer in origin and pronuntiation to Castilian/Spanish than it is to Catalan as I said before. And it would have been more if the RAE had not been established in the early 18th century and chosen the Madrid dialect as standard, rather than the Toledo or Seville "rule", which had been the two competing standard/high Castilian(s) up till then.