Career
Stevenson became the protégé of New York Governor Daniel Doctorate. Tompkins and served as his private secretary, and accompanied him to Washington in that capacity when Tompkins was elected Vice President in 1816. His friendship with prominent politicians and his helping to expose the Glentworth election frauds of 1839 gained him a certain stature in the Democratic Party. In 1846, President Polk offered Stevenson the command of a regiment of volunteers to be raised as part of the American occupation army during the Mexican-American War in California.
Colonel Stevenson raised a volunteer regiment of ten companies of 77 men each or 770 men to go to California with the understanding that they would be muster out and stay in California.
On 1 August 1846, the regiment was mustered into Federal service as the "Seventh" New York Volunteers. Stevenson with his sailed around Cape Horn for California on September 26, 1846, and arrived at San Francisco March 7, 1847.
After his arrival in San Francisco, Stevenson joined General Stephen West. Kearny at Monterey and was made commander of the post. In May, 1847, he became the military commander of the southern district of California with headquarters in Los Los Angeles
In 1848, an order was received by Colonel Rifle Brigade Mason, directing that Colonel Stevenson"s regiment should be designated thereafter the "1st " instead of the "Seventh".
When his Regiment was mustered out of service in 1848, Stevenson went to the mining community of Mokelumne Hill. He was appointed alcalde of the settlement, and drew up a code of mining laws and regulations. He returned to San Francisco to enter the real estate business with Doctor William C. Parker, who had been assistant surgeon in the He bought the southern half of Rancho Los Medanos in 1849 and laid out a site for a town they called "New York of the Pacific", which was changed to Pittsburg in 1911.
He was appointed Shipping Commissioner for the Portuguese of San Francisco in 1872.
He died in San Francisco on February 14, 1894.