Aug. 17, 2022

The United States Annexes California

The United States Annexes California

August 17, 1846. Commodore Robert F. Stockton of the US Navy annexes California during the Mexican-American War.


Cold Open

It’s before dawn on June 14th, 1846 at the Mexican outpost of Sonoma in northern California.

In the darkness, American settler William B. Ide and over 30 American insurgents ride through the town on horseback, headed to the home of Mexican General Mariano Vallejo.

William and his fellow settlers recently heard that California’s Mexican government was threatening to expel anyone in the region who are not Mexican citizens. But many American settlers like William don’t want to leave California. So, tonight, they’re prepared to confront General Vallejo and stage a revolt against the Mexican government.

Soon, the men reach General Vallejo’s adobe home. And there, William dismounts and motions for the group to surround the house. Then, he walks up to the doorstep and knocks.

William hears a stir within the house. But no one comes to the door. The men exchange glances as several minutes pass without any response.

So William pounds again on the door, and then eventually, he watches as it swings open, revealing General Vallejo dressed in his Mexican Army uniform.

Seeing he’s outnumbered, Vallejo raises his hands and then invites William and his associates to come inside for a talk. Reluctantly, William agrees.

Inside, William takes a seat at Vallejo’s dining table. And there, he watches as the Mexican general uncorks a bottle of wine and pours each of the American settlers a glass.

For some time, the men discuss the independence of California from Mexican rule. General Vallejo tries to hear them out. As they talk, some of the men even begin to have second thoughts about their revolt. But William remains unswayed. As other men consider abandoning their plans for revolt and going home in peace… William stands up abruptly. Raising his voice, he issues a forceful declaration, saying: “Saddle no horse for me… Flee this day, and the longest life cannot wear off your disgrace!” 

William Ide’s words will prove convincing. Over the next few days, the American insurgents will imprison General Vallejo, gain control of Sonoma, and proclaim California an independent republic. Together, they will fashion a makeshift flag out of a smock and a petticoat for the new “Republic of California.” And with berry juice, they will emblazon it with a grizzly bear and a star, symbols of strength and sovereignty.

Soon, word of the rebellion will make its way around the region, becoming known as the Bear Flag Revolt. And, in a few weeks, the insurgents will find support from an American military officer who they will elect to head the new “Republic of California.”

But California’s independence will not last. Already at war with Mexico over territorial disputes, the United States will soon intervene. Just 25 days after the Bear Flag Revolt, American soldiers will arrive in Sonoma. And in a matter of weeks, the United States will replace the town’s homemade flag with an American one and begin its conquest of California which the young nation will claim as its own on this day, August 17th, 1846.


From Noiser and Airship, I’m Lindsay Graham and this is History Daily.

History is made every day. On this podcast—every day—we tell the true stories of the people and events that shaped our world. 

Today is August 17th, 1846:The United States Annexes California.

Act One: Conquest of California Begins

It’s the morning of July 15th, 1846 in Monterey, California, the Mexican territory’s current capital.

From a ship in the Pacific Ocean, United States' Naval Commodore Robert F. Stockton looks out at the California coast - the newest object of the United States’ expansionist ambitions.

In recent years, a belief in America’s manifest destiny and a yearning for a country that expands coast to coast has taken hold in the minds of many Americans. Two months ago, this aspiration, in part, pushed the US to formally declare war with Mexico.

The war began because of disputes over Texas’s borders after the US annexed the territory which was previously controlled by Mexico. But the ongoing Mexican-American war is also an opportunity for the US to set its sights beyond Texas, and to extend the nation to the Pacific Ocean by conquering California.

After the Bear Flag Revolt in Sonoma, American naval forces occupied ports across northern California. And last week, these forces bloodlessly captured Monterey after finding the capital city defenseless.

But, the American conquest of California is still incomplete. Even after the capture of Monterey, the commanding general of the region’s Mexican forces, General Jose Castro, has refused to surrender the territory. So, the fight for California continues. And Commodore Stockton is ready to carry it forward.

Today, Stockton is headed to Monterey to relieve the region’s ailing US military leader and replace him as commander of all naval and land forces in California.

Though the morning fog obscures his vision, Stockton can just begin to make out an American flag raised high in the distance. As the morning fog slowly lifts, Stockton guides his flotilla into Monterey Bay. There, he takes charge of the area’s forces and holds control of northern California for the next several weeks. Soon though, the commodore turns his gaze south where Mexican forces have begun to concentrate.

While Stockton orders one battalion to San Diego, he and several hundred other men head to Los Angeles. By August, Stockton’s forces are set up camp just south of the city and prepare for their invasion by drilling and practicing maneuvers. But soon, Stockton's work is interrupted.

Not long after the American arrival outside Los Angeles, two Mexican officers approach the beach outside the Americans’ camp. One of the men reaches into his pocket and pulls out a piece of parchment which he hands to Commodore Stockton.

Stockton gives the Mexican officer a hard stare, before plucking the document from the man’s outstretched hands. He briefly glances over the paper, it’s a letter from General Castro. Stockton looks back up to Castro’s representatives. He motions for them to stay on the beach while Stockton retires to his tent back at camp to examine the letter further.

But as Stockton reads Castro’s proposal to avoid hostilities, indignation fills him. Castro’s terms don’t satisfy Stockton. For him, the only alternative to war is Mexico’s unconditional surrender. So, Stockton rejects Castro’s offer and pens a response with an ultimatum he knows will never be accepted: if Castro agrees to hoist the American flag in California and declare the region independent under the protection of the United States, Stockton will stop his forces and negotiate a treaty.

Stockton places his aggressive suggestion inside a wax-sealed envelope before reemerging from his tent. Stockton then walks over to the Mexican officers still waiting patiently for his response. Stockton hands over his message with a somber declaration: “I will either take the country or be licked out of it.” Then, Stockton dismisses the officers with a flick of his wrist.

Back in Los Angeles, Stockton’s blunt reply angers General Castro. For the Mexican general, surrender is not an option. Even though his army lacks both manpower and resources, Castro believes surrendering would make him a traitor to his country.

Still, the Mexican general worries that the fate of California is already sealed. He knows that he lacks the defenses to properly defend the region. But he also doesn’t want to accept defeat yet. Instead, he concludes that retreat is his only option.

Just a few days after Stockton’s rejected his offer, Castro writes a farewell address to the people of California. With tears in his eyes, the Mexico-appointed Governor of California, Pio Pico, delivers Castro’s address to the legislature in Los Angeles. Then, General Castro, Governor Pico, and a stream of functionaries, officers, and common soldiers flee the city.

After leaving Los Angeles, Castro, and Pico will head to Mexico and ask their government for help. But their pleas will be unsuccessful. With their exit, the Mexican government in California will cease to exist. Abandoned by its defenders, the city of Los Angeles will soon be overtaken by Stockton’s men who will lay claim to one of California’s last bastions of Mexican rule.

Act Two: Siege of Los Angeles

It’s August 13th, 1846 just south of Los Angeles.

With 360 men behind him, Stockton approaches the outskirts of the city. As he looks behind him, the commodore grins.

In the distance, he can see the outline of the other battalion he sent up from San Diego approaching. With the aid of these reinforcements and the strength of his own men, he is hopeful he can successfully occupy Los Angeles.

But Stockton still has some reservations. He doesn’t know what kind of defense is waiting for them in the city. Rumors that General Castro has been fortifying Los Angeles have been circulating for the past month. But estimates of Castros’ forces have varied widely, ranging from 500 to 1500 men. But, today, as Stockton scans the city, he sees none.

Instead, the city appears defenseless. And as Stockton’s men merge with the reinforcements from San Diego, they begin their approach. Marching into the city, Stockton scans the town. Still, he sees no signs of the Mexican military, only frightened, unarmed residents.

And with no Mexican soldiers or officers to stop their advance, Stockton’s forces stride into the center of the city without firing a shot. As the Americans take control, Stockton orders his men to hoist the US flag above Los Angeles. He smiles as he watches the stars and stripes billow high above the town.

And for a moment, Stockton savors the victory. With Los Angeles under American control, his conquest of California feels complete. But Stockton knows it’s not enough for them to just capture Los Angeles, they still need to hold the city.

So, Stockton gets back to work, eager to set up an operation within the city that will sustain American control. With no military opposition to stop him, Stockton declares martial law and a curfew, requiring all residents to be inside their homes from 10 PM until sunrise. Stockton then orders his men to establish a military headquarters on Main Street.

Four days later, on August 17th, 1846, Stockton sits down inside the new headquarters and prepares an open letter addressed to the people of California. In it, Stockton writes that “The flag of the United States is now flying from every commanding position in the Territory, and California is entirely free from Mexican domination.” “The Territory of California now belongs to the United States.” With a flourish, Stockton signs the document, titling himself “Commander-in-Chief and Governor of California."

In the glow of victory, Stockton departs Los Angeles three weeks later, setting sail back to Monterey. But the commander doesn’t abandon the city completely; he leaves several dozen men behind to maintain American control. But Stockton soon realizes his exit was premature.

Though his proclamation establishes American rule in California, it doesn’t end Mexican resistance. Soon after Stockton leaves the city, trouble breaks out. After his departure the small garrison he left behind enforces a tyrannical control of the city’s citizens, upsetting many.

And while there are only 500 to 800 Americans in the territory, there are between 8,000 to 12,000 Mexicans. And, to many of California’s Hispanic population, known as Californios, the Americans are simply invaders. They want them out.

With the departure of Commodore Stockton and the bulk of his men, the city’s Californios sense a vulnerability. In and around the city, they begin to rally together to fight against the new American rule. Soon, an uprising begins. And within two weeks of Stockton's leaving, Los Angeles is in a state of siege.

The Californios surround the city and call for the American surrender. Cut off from supplies and water, the meager American forces have little choice. Within a week of the siege, they surrender and leave the city behind.

But the revolt in Los Angeles will not be an isolated incident. Emboldened by the Californios’ success in driving out the American garrison, the spirit of rebellion will spread throughout the region. Soon, angry Mexican settlers will drive the American forces out of San Diego and out of Santa Barbara. Quickly, the Americans’ reversal of fortune in southern California will bring Stockton back to the region and force the commodore to continue the fight.

Act Three: The Final Battle

It’s the afternoon of January 8th, 1847 near Los Angeles.

Commodore Stockton stands near the banks of the San Gabriel River, with around 600 American soldiers in formation behind him. His men are tired, but determined.

For the past month, the American forces have worked to regain control of San Diego. Finding success there, Stockton turned his attention to recapturing Los Angeles. 

And now, the city is almost within his men to reach. But there is one obstacle still in their way.

Yesterday, US scouts found Mexican forces camped near a ford of the San Gabriel River. Stockton ordered his men closer to gain the initiative, but before he could make plans to attack, Mexican soldiers and cavalry rushed in on the Americans’ left flank, their battle cries ringing out, “viva Los Californios!”

But Stockton and his men hold their line and repel the onslaught. After 90 minutes of fierce combat, the Mexican forces retreat. The next day, they attack a second time but fail again. After the second defeat, many of the Mexican soldiers desert, leaving the path clear for Stockton to retake Los Angeles. Outnumbered, remaining Californios sue for peace and sign a treaty.

But the Mexican-American war will not end with the successful capture of California. Instead, the conflict will continue for another year. And in the end, the US will come out victorious, securing previously-disputed Texas territory, the New Mexico territory, and all of California. But this victory will be controversial, even among many Americans.

Before the war’s end, the Massachusetts legislature will pass a resolution denouncing the war as “a gigantic crime” waged against a “weak neighbor” for the purposes of conquest, territorial aggrandizement, and the extension of slavery. The US House of Representatives will also pass a resolution calling the war an unnecessary and unconstitutional land grab by President Polk. 

And indeed, by the war’s end, Mexico will lose over half of its territory to the United States. America will take another major step toward its goal to span the continent; an ambition critically advanced when Commodore Robert F. Stockton proclaimed California part of the United States on August 17th, 1846.


Next on History Daily. August 18th, 1920. The 19th Amendment is ratified by the United States Congress, granting women the right to vote.

From Noiser and Airship, this is History Daily, hosted, edited, and executive produced by me, Lindsay Graham.

Audio editing and sound design by Mollie Baack. 

Music by Lindsay Graham.

This episode is written and researched by Alexandra Currie-Buckner.

Executive Producers are Steven Walters for Airship, and Pascal Hughes for Noiser.