St. Rose of Lima's birth name was Isabel, but was changed later by her parents to Rose.
When St. Rose of Lima was born on April 20, 1586, her name was Isabel Flores de Oliva. Her parents gave her this name in honor of her aunt, Isabel of Herrera.
However, it wasn’t long until her parents started calling her “Rose.”
This was done because family members thought they saw a rose on her face. This story is told in the 19th-century book The Lives of St. Rose of Lima, the Blessed Colomba of Rieti, and of St. Juliana Falconieri.
The lady Isabel of Herrera, her mother’s sister, being chosen as her godmother, gave her the name of Isabel in baptism; but three months after, as she slept in her cradle, her mother and several other persons, who did not all belong to the family, having perceived on her countenance a beautiful rose, she was called from that time by no other name than Rose on account of this prodigy.
The name was primarily a nickname, until “the Archbishop of Lima [gave] her the name of Rose in confirmation.”
Later on St. Rose was troubled by the name, thinking that it was vain, and focused more on her exterior beauty than on the state of her soul.
It troubled her so much that she cried in anguish to the Virgin Mary.
[H]aving entered the Chapel of the Rosary, she cast herself at the feet of the Blessed Virgin to make known to her her uneasiness. Our Blessed Lady immediately consoled her assuring her that the name of Rose was pleasing to her Son Jesus Christ and that as a mark of her affection, she would also honor her with her own name and that hencefore would she should be called Rose of St. Mary.
This consoled her, and she was finally at peace with the name of Rose.
After her canonization, she would always be depicted in artwork with roses.