The official political movement in the modern Spanish state started in 1922, and since then they have been involved in Spanish politics in a number of ways throughout the 20th century. In the 21st century there have been several other symbolic referenda starting in 2003 when Catalonia elected a coalition of left wing pro-independence parties. I am not particularly qualified to discuss 20th and 21st century Spanish politics as my expertise is in linguistic and Latin American history. However, studying Latin America necessitates some understanding of Western European politics between 1500 and 1900 and the Catalonia issue is very much related to linguistic history so I will attempt to provide some historical context for the 20th and 21st century movements until the arrival of someone who is more qualified to fill in the rest of the details.

It is important to note the modern Spanish state is a relatively recent (1812) invention, and prior to that it had been under the rule of a number of separate regional governments with various levels of sovereignty. The major division that we are concerned with is that of the region at the start of the 15th century. At that time, the kingdom of Castile controlled most of modern Spain, with Granada controlling the south, Navarra a little bit in the north and Aragon (the largest besides Castile) the northeast including Catalonia. The monarchs of Aragon and Castile wed at the end of the century, uniting the two. However, it is important to note that Aragon’s territories (including Catalonia) retained their own laws and governing structures.

In the mid 17th century, the Catalans revolted against Castile but lost, which I guess you could say is the first instance of Catalonian separatism directed at “Spain.” If you want to learn more, look up the Reaper’s War. The next significant event is Charles II’s death at the turn of the 18th century, which triggered the War of Spanish Succession. Aragon backed the Habsburg pretender (the same dynasty as Charles II), but they lost to the Bourbon Philip V and retaliated by ending Aragonese autonomy, creating a new centralized government system in Spain.

Throughout the 19th and early 20th centuries there were a number of local movements in Catalonia to preserve their language and culture as separate from those of Spain, which was largely successful. To this day they still speak Catalan in the region almost as commonly as Spanish (45% vs 35% or so last I saw), although much of the Spanish is from Spanish migrants from outside Catalonia who moved to Barcelona in the mid 20th century. At the turn of the 20th century the majority would have used Catalan as their primary language. This is getting into the time period that I know the least about the internal political movements in Spain as it is post-Latin American independence but the general idea is that there is the beginning of Catalan nationalism and some desire for independence, but never in a major movement until 1922.