Catalan territorial domains in the 14th century, a period of maximum territorial expansion of the Catalano- Aragonese Confederation. Apart from the Principality of Catalonia, its domains streched down to Rousillon, the Kingdom of Mallorca and the rest of the Balearic Islands, the Kingdom of Valencia, the islands of Sicily and Sardinia and the Greek dukedoms of Athens and Neopatras. In the mid 15th century, the Kingdom of Naples was also added.
However, the great Catalan feudal expansion takes place in the 13th century and beginning of the 14th and as a result, the Crown of Aragon extended its Mediterranean domains over Mallorca, Sicily and Sardinia, apart from Valencia. The expansion was started by King Jaume I (James I), who conquered Mallorca in 1229 - from where he expelled the Muslim population - and Valencia in 1238 - a territory that was granted the statute of kingdom and was populated mostly with Catalan people. Subsequently, and coinciding with the great social and economic development of Catalonia in the Middle Ages, the Catalan domains extended over the Mediterranean Sea as far as Sicily and Sardinia.
At the same time, and in the transition from a feudal system to a monarchical state, a political system took shape based on "pactisme", that is, the limitation of royal power by the courts, where the nobility, the clergy and the urban bourgeoisie were represented. This constitutional system gave place to an institution that came into being at the end of the 13th century,
Diputació del General (also known as Generalitat from the 16th century onwards), which gradually acquired political relevance.
Notwithstanding, from the mid 14th century onwards, a period began characterized by demographic (with the recurrent strikes of the plague), economic and political crisis that led the country to the paroxysm of a civil war in the mid 15th century.