Kingdom of Thessalonica

Also known as Regno di Salonicco

The shortest-lived of the Crusader states — a Latin kingdom in northern Greece carved out for Boniface of Montferrat after the Fourth Crusade and conquered by the Despotate of Epirus in 1224.

The Kingdom of Thessalonica was created in the immediate aftermath of the Fourth Crusade, in 1204, when Boniface of Montferrat — the original elected leader of the crusade and the disappointed candidate for the imperial throne in Constantinople — was given the second-largest city of the former Byzantine Empire as compensation. Thessalonica passed nominally under the suzerainty of the Latin Empire, but Boniface ruled it as an effectively independent kingdom with vassals stretching south through Thessaly.

Boniface himself spent most of his short reign on campaign south of his capital, conquering Macedonia, Thessaly, and northern central Greece. He was killed in an ambush by Bulgarians in September 1207, and his infant son Demetrius inherited a kingdom under intense pressure from the Byzantine successor state of Epirus. Regents and a series of weak boy-rulers governed for the next sixteen years.

The end came with the rise of Theodore Komnenos Doukas of Epirus, who had spent the 1210s conquering all of central Greece and Macedonia from the Latin successor states. He took Thessalonica itself in 1224, was crowned 'Emperor of the Romans' in the city, and ended the Latin kingdom altogether. Demetrius fled to the West and lived out his life as a titular king under Hohenstaufen protection. Of all the Latin states of Greece, Thessalonica had been the most powerful at its founding and the briefest in its life.

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