"When Lassen returned to Sutter's Fort he was still haunted by memories of the beautiful scenery in the North Valley. He decided to apply for land and settle there. There were no settlements at all in this region, so there would be room enough for Peter Lassen. Soon after Lassen sent his application for a grant to the Governor of California, General Manuel Micheltorena. The application was filed on October 11, 1843. Peter Lassen applied for: ?A vacant place on the River Sacramento, which is called Bosquejo.'
"Lassen knew that it would take time before he could expect an answer - so in the meanwhile, he would try to apply for naturalization again. He knew this would be a must. The Mexicans had decided that if a man should become a grantee, he should be a Mexican citizen. One year went by, and then on July 25, 1844, his citizenship was stated in Monterey, which at that time was the capital of California. The certificate confirmed that: ??Pedro Lassen, a native of Denmark, having complied with the conditions and requirements prescribed by law for the granting of naturalization letters to foreigners, I have concluded hereby to naturalize the said Don Pedro Lassen by virtue of the powers conferred on me by said law.' It was signed by Micheltorina. Lassen got his citizenship exactly four years after his arrival in California. Five months later, on December 26, 1844, Lassen's grant was approved by the Mexican Government.
"Lassen got 5 square leagues of land, which is approximately 22,000 acres. Soon after, Peter Lassen started out from Cosumnes River with his cattle, horses and mules. His destination was: Bosquejo, at the Sacramento River. Lassen and his housekeeper, the Dutchman, Sargent, knew that they had to be patient and take their time. When they reached Cordua, now Marysville, the river had become flooded, and they had to wait at least a month before, in February 1845, they were able to continue. Soon after they reached what became Peter Lassen's new home. Lassen's housekeeper soon learned that this "nowhere" was not what he wanted, and he disappeared. Lassen was now the only white man here - living alone among the Indian tribes - only having his herd of cattles, horses and mules around. To be all alone in the beautiful nature, must have made him happy.
"People who knew Lassen later told that it was his idea to build a town at this spot. Lassen's property had many names, Lassen Grant, Lassen's Ranch or the Spanish form, Lassen Rancho are the most common names. It was also called Deer Creek Ranch - but Lassen, obviously in honor of his new naturalization in a Mexican vassal state gave it a Spanish name: Bosquejo Rancho. Bosquejo means wooded land - so today we can visualize how the place was looking."
from "Uncle Peter" pages 62-63