Mystras is a Byzantine ruined city near the village of the same name, northwest of Sparta.

The history of Mystras begins with the Fourth Crusade. When the Crusaders conquered the Peloponnese in 1206/1207, Godfrey I of Villehardouin became Prince of Achaea. His son, William II, conquered the rest of Laconia and in 1249 built a strong hilltop fortress in Mystras, which had previously been uninhabited.

In 1259, William II was captured by the troops of the Byzantine Emperor and secured his release by surrendering Mystras. The Greek inhabitants of Sparta, weary of Crusader rule, settled in Mystras, located just three kilometers away. A flourishing city grew up below the castle, eventually boasting a population of tens of thousands.
Mystras was conquered by the Ottomans in 1460. Minarets began to appear alongside churches and monasteries. The city came under Venetian control in 1687, but fell back to the Ottoman Turks as early as 1715.

In 1770, during a Russo-Turkish war, troops from the Balkans, who had invaded the Peloponnese on Ottoman orders, devastated the city. This marked the end of Mystras's heyday. During the Greek War of Independence, the city was subsequently so severely destroyed that plans for its reconstruction were abandoned. Instead, a short time later, Sparta, which had been abandoned centuries earlier, was rebuilt.

Mystras has been a UNESCO World Heritage Site since 1988.

The Church of Hagios Demetrios, the earliest of the surviving churches of Mystras, is the metropolitan church, It is a wooden roofed basilica.

The church was founded between 1263 and 1272 by the Bishop Eugenios, whose tomb was discovered in the church. The paintings were commissioned by Bishop Theodosios and date to approximately 1272.
Inscriptions dedicate the structure to Nikiphoros, Metropolitan of Laconia, however, he was undoubtedly not the founder, he likely only commissioned the construction of the narthex around 1310.