Lawrence Rainwood was the Chief Overseer of The Order as of 1985. During the late 1950s, he founded the Rainwood Day Camp & Learning Center. Lawrence was never married but had a son, Jacob, who also became a member of The Order. Jacob later took Lawrence's position as Chief Overseer, presumably after his death.
It has been heavily implied that Lawrence was somehow betrayed by conspirators within The Order, which likely resulted in his death.
KindVonDerRitter's video titled 'Memoir' implied that Daniel Shipman was to deliver a message to Chris and Alex, and also mentioned a key, ROT, and a "weapon" to destroy The Order, which could be found in New Jersey. Around late 2012 or early 2013, a woman stopped Daniel on the street outside of a church having a late-night sermon and handed him an envelope. Inside was a letter addressed to him as well as a key. Daniel, along with Chris and Alex, used the key to enter a locked door in the Rainwood Day Camp, where they found a locked chest which opened with the combination "0304" (the 3rd World to the 4th World). The paper within the chest was marked with a code decipherable with ROT, which mentioned Lawrence.
Following the code, the three deciphered a series of additional codes using unmarked books found in a local library, each of which had the theme of betrayal. The main code ultimately solved to "My conspirators are among you?", leading them to believe that Lawrence may have known he was being betrayed, and mentioned Brandt-Crater, a cemetery. The three discovered a slab marked with The Order's symbol, which an Overseer would stand on while leading a meeting, frozen into the ground behind a mausoleum labeled "Ritter" at the back of the cemetery. On the bottom of the slab was a map seemingly leading to a specific part of the cemetery, the significance of was never discovered due to three members of the Order chasing Chris, Alex and Daniel out of the cemetery with a gun. Daniel tried to return alone later on but give up as soon as he saw a police crew investigating the area, knowing they were in cahoots with the Order.