There is a legend, which is supported by a substantial amount of circumstantial fact, that in 1829, a Padre from a mission in San Rafael (Mission San Rafael Archangel) had rode a horse up into Sonoma County looking for native Americans to convert. He was riding along the banks of a creek when he was attacked by a group of local Native Americans. He fled the attacks, stopping briefly to baptize (then capture) a young indian woman whom he'd came upon along the creek. This event took place on the feast day of Saint Rose of Lima, so he named the girl (and creek) Santa Rosa
The City of Santa Rosa gives this legend enough merit that a stone and plaque were place at the location where this event reportedly took place.
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