The Soteria were ancient festivals held in many Greek cities from the 3rd century BC. They honoured the saviour (Sôter) of a danger and could be dedicated to all the gods or only one (mainly Zeus

Zeus

In the ancient Greek religion, Zeus was the "Father of Gods and men" who ruled the Olympians of Mount Olympus as a father ruled the family. He was the god of sky and thunder in Greek mythology. His Roman counterpart is Jupiter and his Etruscan counterpart is Tinia.Zeus was the child of Cronus...

 Soterios). Heroic men regarded as deliverers were sometimes associated to the divinities, e.g. Aratus

Aratus

Aratus was a Greek didactic poet. He is best known today for being quoted in the New Testament. His major extant work is his hexameter poem Phaenomena , the first half of which is a verse setting of a lost work of the same name by Eudoxus of Cnidus. It describes the constellations and other...

 at Sicyon

Sicyon

Sikyon was an ancient Greek city situated in the northern Peloponnesus between Corinth and Achaea on the territory of the present-day prefecture of Corinthia...

.

The most famous Soteria in the antiquity were those held at Delphi

Delphi

Delphi is both an archaeological site and a modern town in Greece on the south-western spur of Mount Parnassus in the valley of Phocis.In Greek mythology, Delphi was the site of the Delphic oracle, the most important oracle in the classical Greek world, and a major site for the worship of the god...

. They had been instituted to commemorate the victory over the Celt

Celt

The Celts were a diverse group of tribal societies in Iron Age and Roman-era Europe who spoke Celtic languages.The earliest archaeological culture commonly accepted as Celtic, or rather Proto-Celtic, was the central European Hallstatt culture , named for the rich grave finds in Hallstatt, Austria....

 invader Brennus

Brennus (3rd century BC)

Brennus was one of the leaders of the army of Gallic invasion of the Balkans, defeated the assembled Greeks at Thermopylae, and is popularly reputed to have sacked and looted Delphi, although the ancient sources do not support this.In 280 BC a great army, comprising about 85,000 warriors, coming...

 (279 BC). They were composed of sports and musical competitions. Many cities were invited to the Delphi’s Soteria. In 246 BC, the Aetolian confederacy reorganized the festivities in order to equal others ancient games (Pythian games

Pythian Games

The Pythian Games were one of the four Panhellenic Games of Ancient Greece, a forerunner of the modern Olympic Games, held every four years at the sanctuary of Apollo at Delphi....

...).