In the late 1950s Landis was entrusted with a large collection of papers from Christian E. Charles, one of the deacons at Landisville Mennonite Church. No longer able to house these documents at his home, he founded the Lancaster Mennonite Historical Society in 1958 to store and maintain the new archive. Under Landis, the society continued to grow and he founded the Mennonite Research Journal in 1960.
