L.B. Hartz was born in Duluth, Minnesota in 1895. He attended elementary and high school there. After graduating from high school he managed a truck farm for several years. In World War I he served with the First Army in France as a munitions truck driver. After the war, Hartz attended the Duluth Business University [DBU] where he studied accounting. For the next four years he worked as a bookkeeper or with credit associations. For one season he taught accounting at DBU. Prior to opening his own store, Hartz represented a credit association in the liquidation of five bankrupt stores. In 1925, in Roseau, Minnesota, Hartz opened his first store. He went on from there to own and operate one of the largest chains of stores in the area.
The L.B. Hartz Papers contain the business ledgers for L.B.Hartz, Inc. dating from the early 1940s through the 1960s. It also contains the various deeds, income tax returns, insurance policies, inventories, leases, and correspondences and other written records of the company. Also included is a scrapbook containing the articles of incorporation for the Hartz Foundation and United Industries.