How the Santa Ana River Got its Name

I have a book in my collection called California Place Names by Erwin G. Gudde (4th edition).  According to this book, the Santa Ana River is named for St. Anne, the mother of the Virgin Mary. It was named on July 28, 1769 by the Portola expedition when it camped by the river. The soldiers named it Santa Ana and this appears to be the only time on this expedition that the soldiers (as opposed to the padres) gave a place a holy name. Potola did not camp beside the river in our area, but the Santa Ana stretches all the way to the Pacific Ocean, leaving him and his expedition plenty of places to camp!