Frederick II was the Holy Roman Emperor from 1220 to 1250 and is considered to be one of the most influential Holy Roman Emperors of the middle ages. At the age of 3 he had been named King of Sicily and ruled alongside his mother, Constance. He was a big promoter of science, art, and culture.
Frederick II commissioned a number of castles and cathedrals in Puglia. The most notable is Castel del Monte, unusual for its octagonal shape. Frederick’s son, Manfred, married Helen of Epirus in the castle at Trani, another castle built by Frederick II. Lucera Castle has some features similar to Castel del Monte.
He also commissioned several cathedrals such as the Romanesque cathedral of Altamura.