Kingdom of Italy, rewarded for changing sides in the First World War, annexed it according to the secret Treaty of London and later Treaty of Rapallo. After World War II, it was split between Italy (West), Slovenia (North), and Croatia (South).
Trieste had strategic importance as Austria-Hungary's primary seaport and the coast of the Littoral was a resort destination, the Austrian Riviera. The region was a multi-national one, with Italians, Slovenes, Croats, Germans and Friulians being the main ethnic groups. In 1910, it had an area of and a population of 894,287.