Ontario and the Jurupa Hills and Rancho

In 1838, the Mexican government granted him Rancho Jurupa in modern-day San Bernardino County and Riverside County.[3

The exact meaning of the word "jurupa" is disputed. The 1890 book, An Illustrated History of Southern California, states that the word was a greeting, meaning ″peace and friendship″, used by the Native Americans when the first Catholic priest visited the area.[10] In 1902, Father Juan Caballeria, in his History of San Bernardino Valley; From the Padres to the Pioneer, states that the word was derived from jurumpa, meaning watering place.[7] Later linguistic studies concluded that the name likely refers to juru, Artemisia californica (California sagebrush), common in the area.

During the brief Mexican–American battle for California, Bandini supported the Americans and even issued an appeal to not resist the Americans. After the war, Bandini was increasingly critical of the U.S. government, especially the Land Act of 1851 that allowed Mexican land grants to be challenged. The Treaty of Guadalupe Hidalgo with Mexico, in 1848, had guaranteed the land grants would be recognized and while most of them were eventually successfully defended, the expense bankrupted many in the process and they had to sell off large portions of their holdings to cover legal fees.

Bandini liked to dress elegantly, was always gracious, and maintained a refined presence wherever he went. He was known as a charming public speaker, fluent writer, excellent dancer, fair musician, and fine horseman.

Richard Henry Dana Jr. in Two Years Before the Mast said of him:

"He had a slight and elegant figure, moved gracefully, danced and waltzed beautifully, spoke the best of Castilian, with a pleasant and refined voice and accent, and had throughout the bearing of a man of high birth and figure."

Seeing him again one evening, Dana said:

"He gave us the most graceful dancing that I had ever seen. He was dressed in white pantaloons, neatly made, a short jacket of dark silk gaily figured, white stockings and thin Morocco slippers upon his very small feet."

Imagine cattle on a thousand hills as you pass through Rancho Jurupa, no homes, just a vast valley and foothills and brilliant horsemen tending to their herds under a hot summer sun.