Hazel (Woolsey) Warren worked at a bank in Tecumseh. Later, she worked for a local newspaper qualifying as a linotype operator. After her marriage to Keith Warren , the couple managed the Kayenta Trading Post in Kayenta, Arizona, until 1935. They then managed the Cedar Ridge Trading Post in Cameron, Arizona, until their retirement in 1949. Upon retirement, the couple traveled extensively for a time in the western United States and western Canada before settling in Phoenix, Arizona.

Hazel Warren was an avid writer. She began journaling in childhood and continued to keep journals for most of her life. Ms. Warren began submitting feature articles to magazines and newspapers for publication in the late 1920s.  In addition to magazine articles, Ms. Warren wrote a column during the 1940s that was published by The Punxsutawney News in Punxsutawney, Pennsylvania. Ms. Warren also was a hobbyist who enjoyed collecting decals and buttons, among other things, and her column titled "Indian Lore" was published in nationally-distributed hobby magazines during the 1940s.

Papers of writer and Indian trader Hazel Warren. Papers include professional correspondence with publishers; scrapbooks containing news clippings, photographs, published articles and other items; daily journals and vacation journals; a decal collection with decals obtained from places visited as well as decals distributed in support of the war effort during World War II; personal items that belonged to her husband Keith Warren; published magazine articles authored by Ms. Warren; and published and unpublished manuscripts of feature articles and short stories (she authored some articles under the name "H.W. Warren" as well as others under the pseudonyms "Louise R. Marshall" and "Beatrice Warren"). While many of these manuscripts are typewritten, the bulk of them are handwritten (Note: Ms. Warren often recycled paper and would type new articles on the backs of older handwritten articles).