John R. Oishei was born in Buffalo in 1886 to Charles Humbert Oishei and Julia (Roffo) Oishei.
Oishei was one of eight children to Charles and Julia: John R. Oishei, Stella Oishei, Camilla Oishei, Bertha Oishei, Charles Oishei Jr., Bernard Oishei, Florence Oishei, and William Oishei.