The Secret Society was started by the old Kazekage Magus after the destruction of Sunagakure. Its primary goals were thet wellbeing of the shinobi world at-large. Their leader, Magus, was often in disguise as one of any sort of wandering character. He oftentimes would heal or train shinobi from various villages.
The Society had several different ideals of possible ways to help the shinobi world. One was the distribution of power, such as kekkei genkai or jinchuuriki evenly through the world, another was that the world would be best off with minimal wars.
The society is currently disband after the events of the Shinobi World War 5 that Maguscaused creating an abomination that weilded the rinnesharingan via a hordering of power.