The hill where the Jumilla castle is built was inhabited by people from the Bronze Age. In a later era, this was occupied by people when Iberian civilizations were present in large part of Iberian Peninsula, and specifically in the current municipality. In Roman Iberian Peninsula period, people also leveraged this hill. The last era in regards to this hill before the construction of the current castle is the one when large part of Iberian Peninsula was under Muslim peoples rule. They built a fortress in the 8th century, but they used unstable materials.
In 1241 Jumilla Castle was conquered by troops of Ferdinand III of Castile. Around 1290 the area passed to the Kingdom of Aragon. In 1357 the castle was taken by Ferdinand of Aragon, who had sided with Peter of Castile. Shortly after, Ferdinand again pledged his obedience to his brother, Peter IV of Aragon. Thus the castle returned to the Aragonese crown. In 1358 the castle was again taken for the Castilian crown by Fadrique Alonso, Lord of Haro and Master of the Order of Santiago.
The current castle was built in the year 1461 and its architectural style is gothic.
Towering 52 meters above the sea, Bengtskär lighthouse is the tallest one in Scandinavia. The building started in in 1905 after the shipwreck of S/S Helsingfors and was completed in 1906. The lighthouse was designed by architect Florentin Granholm. On December a special petrol lantern, designed and built in Paris, was brought to Bengtskär and installed atop the tower.
German fleet bombarded Bengstkär in the First World War in 1914. Since the Gulf of Finland was heavily mined, it was not until 1919 that the surrounding seas were declared safe for shipping, that the light was lit again.
After the war the military value of Bengtskär increased as part of the defence system of independent Finland. In Second World War (1941) Soviet Union made a suprise attack to island. After a bloody battle, the small Finnish garrison emerged victorious. Intermittent repairs to the facility continued during the post-war period.