Not to be confused with Main article: The Pirate Republic The Brethren Alliance was the main force that was responsible for a number of crushing defeats dealt to Leon's forces from October leading into mid-December. The formation of the alliance was caused by the creation of the 5th Brethren Court, and each of the Pirate Lords allied with each other, as well as other guilds. In the end, it would comprise over a dozen guilds.