The Suit of Sorrows was created in 1190 during the Crusades, and given to a Knight, Sir Geoffrey De Cantonna who was supposedly pure of heart. The suit drove him insane, and he slaughtered several hundred people in a remote Alpine valley. To protect the knight's reputation, there was a cover-up that claimed that the Moors were responsible.
The Suit was originally forged by the Order of Purity, a splinter sect of the Order of St. Dumas. The armor was crafted and forged from the melted blades and breastplates of several soldiers of the Order who had fallen in battle. The Suit was originally designed to be worn by the Order of Purity's champion, Azrael, but it was always in exchange of a great personal price.
Years later, the armor was bestowed upon Batman by Talia al Ghul as a gift, and although it made him significantly stronger and faster, he was forced to stop using it when he began to believe it was somehow corrupting him and making him more violent. However, Batman was unable to bring himself to destroy the artifact, and instead chose to store it on display in the Batcave. After Batman's disappearance from Gotham City, the suit was stolen from the Batcave.
First, this suit was used by Abraham Arlington for only six weeks; but after his mental breakdown, the Order of Purity took the suit away from him and gave it to Michael Lane, who whould be their new Azrael.
On Prime Earth, the Suit of Sorrows worn by Jean-Paul Valley has a highly advanced artificial intelligence implanted inside of it that interfaces with the wearer's nervous system, telling him where and when to strike. Lucas Fox compares it to having two brains in one body, enough to drive a man insane.