The Danish sea captain Cornelius Jensen settled in Agua Mansa around 1854 where he ran a store, and he married Californio Mercedes Alvarado soon thereafter. After the Great Flood of 1862, most of the town was destroyed with the exception of the cemetery, the chapel, and Jensen's store. Some years later, Jensen bought a part of the Rubidoux ranch. Jensen and Alvarado bought land in Agua Mansa in 1865.