Nothing to add, but I am curious about the works you mentioned. Can you give names. I have never studied this historiography, but it is fascinating it seems.

I don’t think this question has a settled answer among historians at the moment. And I am not sure that really any of them describe what happened particularly well.

It was a single revolution in that so many creole developed a sense of frustration with the status quo, and when they received an opportunity to advance their own interests, they did. And I suppose the definition of the word revolution fits pretty well with what happened (according to merriam-webster: “the usually violent attempt by many people to end the rule of one government and start a new one” or “a sudden, extreme, or complete change in the way people live, work, etc.”). The period might also be considered a singular revolution because many of the independence armies supported each other in their campaigns. Taken from a distance, Bolívar to the north and San Martín to the south acted as a large pincer movement against royalist strongholds. But thinking about the break as a single revolution does not always work well because there was not much political unity or solidarity among any of the creole and plebeian groups scattered in the Western Hemisphere leading up to and during the break with Spain. The first leaders of the Mexican independence movement had far different views and intentions than those in the Río de la Plata. Also, the break with Spain was not premeditated, nor were people imagining independent nation-states, so they did not really start at the same moment.

Perhaps then describing the period as a series of revolutions would be better a better description? Though some of the military campaigns complimented each other, much of the revolutionary political movements happened independently of others. The leaders tended to look inwards toward the localities since power reverted back to the people in the absence of a king. Only after a few years did the local juntas begin moving towards independence. However, a ton of historians have spent the last 30 years pointing out that these revolutions weren’t nearly as revolutionary as their famous leaders gloriously described in their Enlightenment prose/oratory. It’s also problematic that people considered themselves loyal to the Spanish Crown well into the revolutionary period. Though many creoles were upset with the discrimination, it was evident to many in the New World that change was coming via the reform minded Bourbons. Merchants had already seen modest trade liberalization and governmental reorganization. Revolutions weren’t really needed as much as some have described. Calling it a series of revolutions also doesn’t fit particularly well since initially many of the independence periods started with unifying movements that sought to put together or hold together disparate groups of people.

Calling it a civil war frees this period from the constraints of terms like empire and revolution, according to Jaime E. Rodríguez O., whom I think is the most famous of the civil war proponents. Calling it a civil war between Spaniards allows historians to think about the continuities of Spanish identity among those who called for change and explains why the colonies did not break immediately from Spain. He also uses the civil war thesis to explain how those who drove for independence saw it as an opportunity to complete and/or renegotiate the previously mentioned reforms. But according to Jeremy Adelman in The Oxford Handbook of Latin American History, “dispensing with structured notions of asymmetry and inequity makes it hard to explain the violence and discord that followed the crisis of 1808. While Rodríguez challenges both the view that creoles were bound to defy imperial authority and the structuralist assumption that the old regime could not adapt to modern mores, he is forced to restore the Liberators back to the center of the political stage, albeit shorn of their heroic vestments, as the saboteurs of the system” (169). There were so many subalters who participated in the the revolution: indigenous people, free blacks, and slaves. Were they too fighting in a Spanish civil war as Spaniards?

To add another wrinkle, many historians have pointed out that the revolutionary period didn’t really end until the revolution/revolutions/civil wars crystallized into the modern nation-states that replaced the Spanish system. That means that the revolution/revolutions/civil war lasted until the 1880s in some cases. If you include the Bourbon Reforms as the impetus for the disruption, that’s almost 200 years of reform and transition, which doesn’t fit very well with the concepts of abrupt change or passing internal strife. The period also does not fit with our concept of nation-state, since this was the end result of the 200 year long transition.

For me personally, the continuities between the old system and the early national period are powerful. The long duration of state formation indicates that maybe the period was a realignment in the whole system rather than an event that fit into simple categories. Additionally, I am struck by the contingency of the whole thing. The results of the transition could have turned out very differently; nothing about them was foreordained. So maybe each of the three terms is as right as it is wrong and can all be used at the same time. Maybe some combination of the multiple revolutions thesis and the civil war thesis mixed together with a long term view as a transition period and a whole pile of other inherited baggage would be better than any of the three on its own.

I came across this older thread when researching for a current question - maybe the current one might be interesting for your questions, altough the discussion focuses more on influences on than definitions of the Spanish American wars of independence.