Denver's Catholic archdiocese is studying whether a former slave known for her service to her neighbors should be named as a saint.
A mass Sunday at the Cathedral Basilica of the Immaculate Conception will officially open the canonization process for Julia Greeley.
Greeley was born into slavery in Missouri in the mid-1800s and came to Colorado around 1880. She worked as the housekeeper for the first territorial governor of Colorado, William Gilpin, and later became known for her charity work.
Greeley is one of four people that U.S. bishops voted to allow to be investigated for possible sainthood at their fall meeting.
The first step in the process involves gathering testimony and documentation about her life. A report will be sent to the Vatican, which will decide whether to proceed.