By Joe Novitski and Larry Clinton, Sausalito Historical Society
In 1845, President James K. Polk proposed to purchase Alta California and Santa Fe de Nuevo México from Mexico, and to establish the Rio Grande river as the southern border of United States. After Mexico rejected that offer, the U.S. declared war on May 13, 1846.
It took almost three months for news of the war to reach California. Meanwhile, Mexico had proclaimed that unnaturalized foreigners were no longer permitted to have land in California and were subject to expulsion. American settlers in the Sacramento Valley banded together to meet the threat. Captain John C. Frémont, who was leading a U.S. Army topographical expedition to survey the Great Basin, decided to get into the war instead. He joined the settlers and offered advice to capture the Northern Headquarters of General Mariano Vallejo at Sonoma. On June 14, the “Osos” – as they called themselves -- took the town of Sonoma at dawn without firing a shot. With General Vallejo's surrender the Osos declared California a Republic and raised the Bear Flag over the plaza.
Commodore John D. Sloat, commander of the U.S. Navy's Pacific Squadron, had received orders to seize San Francisco Bay and blockade California ports when he was positive that war had begun. Under the command of John B. Montgomery, the sloop-of-war USS Portsmouth was ordered to seize the port of Yerba Buena, the future San Francisco.
Joe Novitski, a resident of Kappas Marina, recently gave a presentation on the Mexican-American war at the Sausalito Yacht Club, in which he described how the Portsmouth first arrived at Sausalito. Based on entries from the ship’s log, which Joe found at the National Archives, it took Montgomery the “better part of that day with Gate in sight to get into Sausalito at 0720” on June 3.
Two days later, the Portsmouth sent a launch into Sausalito loaded with “flour, pork iron and other provisions requested by Captain Frémont commanding the U.S. A. Topographical Exploring Expedition at his camp.” For the next few days, “small arms men and marines” went ashore to practice firing at targets in preparation for a landing in Yerba Buena.
On June 24, according to the log, "Mr. Richardson came aboard as pilot." That would be William Richardson, the founder of Sausalito and one-time port captain of Yerba Buena. The Portsmouth got underway “under topsails jib and spanker for Yerba Buena anchorage.”
On July 5 Frémont's California Battalion was formed by combining his forces with many of the Bear Flag rebels to occupy Yerba Buena.
For the next several days, various forays were made from the Portsmouth to communicate with Captain Frémont, to protect American citizens, and to retrieve and treat wounded men. On July 9, 1846, 70 sailors and marines landed at Yerba Buena and raised the American flag over the plaza that today is known as Portsmouth Square. Later that day in Sonoma, the Bear Flag was lowered, and the American flag was raised in its place. The Portsmouth remained in San Francisco Bay until November 1846.
In 1847 the U.S. Army, under the command of Major General Winfield Scott, captured Mexico City. Fort Winfield Scott in the Presidio is named for the general and is now being transformed into a campus for environmental and/or social change. The 1848 Treaty of Guadalupe Hidalgo ended the war and specified the cession of of Alta California and Santa Fe de Nuevo México to the United States. That was just a year before the Gold Rush put California on the fast track to statehood.