Demetrius of Thessaloniki was a Christian soldier and martyr who lived in the early 4th century. Born into a senatorial family in Thessaloniki, he reportedly served as a proconsul in the region. He was executed around 306 during the persecutions under Emperor Galerius, dying by being run through with spears. Known as the Myroblyte because his relics were said to emit a fragrant myrrh, he is venerated as a great martyr and is considered the patron saint of Thessaloniki.