The Cult of Ares was an ancient order that was dedicated to the Greek God of War known as Ares. In that era, he was defeated by the Amazon Queen Hippolyta and imprisoned by his father Zeus for his crimes. Despite his capture, the Cult continued to exist even in the modern era where they hid their activities amongst mankind and waited for the return of their master. Once Ares was freed from Themyscira, the Cult of Ares quickly moved to support their master leading to Diana uncovering their base during her mission to recapture the God of War.
The Cult of Ares features in the 2009 Wonder Woman animated movie.