Mystras, the ‘wonder of the Morea’, developed down the hillside from the fortress built in 1249 by the prince of Achaia, William II of Villehardouin, at the top of a 620 m high hill overlooking Sparta.
The Principality of Achaea was one of the three vassal states of the Latin Empire which replaced the Byzantine Empire after the capture of Constantinople during the Fourth Crusade. It became a vassal of the Kingdom of Thessalonica, along with the Duchy of Athens, until Thessalonica was captured by Theodore, the despot of Epirus, in 1224. After this, Achaea became for a while the dominant power in Greece.
The Franks surrendered the castle to the Byzantines in 1262, it was the centre of Byzantine power in southern Greece, first as the base of the military governor and from 1348 as the seat of the Despotate of Morea. Captured by the Turks in 1460, it was occupied thereafter by them and the Venetians.
Today impressive ruins of Villehardouin's Castle still remain.
References:The Church of St Donatus name refers to Donatus of Zadar, who began construction on this church in the 9th century and ended it on the northeastern part of the Roman forum. It is the largest Pre-Romanesque building in Croatia.
The beginning of the building of the church was placed to the second half of the 8th century, and it is supposed to have been completed in the 9th century. The Zadar bishop and diplomat Donat (8th and 9th centuries) is credited with the building of the church. He led the representations of the Dalmatian cities to Constantinople and Charles the Great, which is why this church bears slight resemblance to Charlemagne's court chapels, especially the one in Aachen, and also to the Basilica of San Vitale in Ravenna. It belongs to the Pre-Romanesque architectural period.
The circular church, formerly domed, is 27 m high and is characterised by simplicity and technical primitivism.