Louis III of Naples

Louis III (25 September 1403 – 12 November 1434) was titular King of Naples from 1417 to 1426, Count of Provence, Forcalquier, Piedmont, and Maine and Duke of Anjou from 1417 to 1434, and Duke of Calabria from 1426 to 1434.

He was the eldest son and heir of Louis II of Anjou and Yolande of Aragon.

The throne of Aragon fell vacant in 1410 (Louis was then 6 years old) when king Martin I of Aragon died. Louis' mother Yolande was the surviving daughter of sonless King John I of Aragon, Martin's predecessor. They claimed the throne of Aragon for the young Louis.

However, unclear though they were, the succession rules of Aragon and Barcelona at that time were understood to favor all male relatives before any female (this is how Yolande's uncle, Martin of Aragon, inherited the throne of Aragon). Martin died without surviving issue in 1410, and after two years without a king, the Estates of Aragon by Compromise of Caspe in 1412 elected Infante Ferdinand of Castile as the next King of Aragon. Ferdinand was the second son of Eleanor of Aragon and John I of Castile. The family however had secured some Aragonese lands in Montpellier and Roussillon.

Yolande and her sons regarded themselves as heirs of higher claim and began to use the title of Kings of Aragon. From this "inheritance" forward (Aragon added to other Angevin titles), Louis and Yolande were called the King and Queen of Four Kingdoms, those four being Sicily (including Naples), Jerusalem, Aragon, and Majorca. Of those, only the mainland part of Sicily was ever directly held by Louis, and only briefly. Louis also had claims on the title Latin Emperor, which his grandfather Louis I had purchased in 1383, but he never appears to have used this title.

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