Materials in Subseries 1.1 are from the first generation of Yasui family members who immigrated to the U.S. at the beginning of 20th century. Letters to and from Masuo Yasui, Renichi Fujimoto, and Shidzuyo (Miyake) Yasui are usually personal in nature and written between family members in pre-World War II Japanese, with a small amount of business- and community-related correspondence included. While most of this early correspondence predates World War II, some correspondence is from the period when Masuo Yasui and other family members were incarcerated by the U.S. government in separate locations.