Sergius (or Serge[4][5]) and Bacchus (Greek: Σέργιος & Βάκχος; Classical Syriac: ܣܪܓܝܤ ܘܒܟܘܤ, romanized: Sargīs wa Bākūs; Arabic: سركيس و باخوس, romanized: Sarkīs wa Bākhūs, also called Arabic: سرجيس و باكوس, romanized: Sarjīs wa Bākūs)[6] were fourth-century Syrian Christian soldiers revered as martyrs and military saints by the Catholic, Eastern Orthodox and Oriental Orthodox Churches.

According to their hagiography, Sergius and Bacchus were military officers in the army of the Roman Emperor Galerius and were held high in his favor until they were exposed as secret Christians.

They were then severely humiliated and punished, forced to wear both feminine and commoner garments, with Bacchus dying during torture to his feet, and Sergius eventually decapitated.

Sergius and Bacchus were very popular throughout Late Antiquity for their fraternal and pious relationship, and churches in their honor were built in several cities, including Constantinople and Rome.

The close friendship between the two is strongly emphasized in their hagiographies and traditions, making them one of the most famous examples of paired Christian saints.

The story is ostensibly set during the reign of Roman emperor Galerius (305 to 311), though it contains a number of contradictions and anachronisms that make dating difficult.

After they persisted in refusing to sacrifice to Jupiter in Galerius's presence, they were publicly humiliated by being chained, dressed in female attire and paraded around town.

The construction of this Church of Saints Sergius and Bacchus, between 527 and 536 AD (only a short time before the erection of the Hagia Sophia between 532 and 537), was one of the first acts of the reign of Justinian I.

The close friendship between the two is strongly emphasized in their hagiographies and traditions, making them one of the most famous examples of paired saints; the scholar John Boswell considers them to be the most influential set of such an archetype, more so than even Peter and Paul.

[12][13] In his Same-Sex Unions in Premodern Europe, Boswell further argues that Sergius and Bacchus' relationship can be understood as having a romantic dimension, noting that the oldest text of their martyrology describes them as erastai, which can be translated as "lovers".

There is no evidence for Sergius and Bacchus's schola gentilium having been used by Galerius or any other emperor before Constantine I, given that the persecution of Christians had begun in the army considerably before the 4th century.