The initial reluctance of the ruler of the Californias, José Ma. Arguello, was followed by the arrival of the Englishman Thomas Cochrane and his fleet to the coast of Baja California. Cochrane, who had fought alongside Chilean independence fighters, was seen as a pirate on the peninsula.

His arrival fueled suspicion, leading Lieutenant Fernando de la Toba to precipitate the swearing of independence in San José del Cabo on March 7, 1822. Later, Lieutenant José María Mata in Loreto and Lieutenant and Commander José Manuel Ruiz in the mission of San Vicente did the same.

In June 1822, the imperial commissioner, Canon Agustín Fernández de San Vicente, arrived in Loreto to secure the province's adherence to Emperor Agustín de Iturbide's regime and establish the first municipal governments.

Hacia 1825 José Ma. de Echeandía, jefe político del momento, hizo una reorganización política tomando algunas de las antiguas misiones como cabeceras distritales y reglamentó la dotación de tierras comunales a los indios sin intervención de los religiosos. Este proceso inicial de secularización no tuvo éxito.

The inconsistency in the policies regarding ecclesiastical properties and privileges favored the survival of the missions and their temporalities. However, their role as a form of social organization and economic production no longer had a future. As a result, they gradually transformed into secular towns.

Around 1829, the same area located in a broad valley along the river called Tijuana, surrounded by multiple hills and canyons, was granted to the Californian military and politician Santiago Argüello Moraga, under the name "Tía Juana."

By February 1888, Tijuana functioned as a municipal commission, dependent on the municipality. July 11, 1889, is considered the official founding date of the city of Tijuana.

20th Century 

At the beginning of the 20th century, in 1900, Tijuana was a small settlement with only 245 inhabitants. The only residential area was the city center, and the main avenue was Calle Olvera (now called Avenida Revolución), where some businesses and shops catered to tourism. In 1901, it became the first sub-prefecture of the municipality.

In 1925, the name was changed to Zaragoza, but this change didn't progress, and the original name continued. It was only in 1953, with the creation of the state of Baja California, that the municipality of Tijuana was officially established, with this city as its seat.

The 1920s brought significant events. The so-called "Prohibition" in the United States, which banned the sale of alcoholic beverages, motivated numerous Americans to seek what was denied to them in their country on the border.

Soon after, gambling was authorized in Mexico, leading to the opening of important casinos like "Agua Caliente" in Tijuana. During this time, the Álvaro Obregón School building was also constructed, considered one of the best educational institutions in the country at that time.

The international events of the 1940s had profound repercussions in Tijuana due to World War II.

Many tourists from the neighboring country visited the city's nightclubs, and there was a significant increase in migration from the interior of Mexico, as people sought better job opportunities in the United States. As a result, Tijuana's population nearly tripled in that decade.

Starting in 1974, the regeneration of the Tijuana River area began, becoming the most important national urban development project, covering an area of 400 hectares and transforming the city into one of the most modern and urbanized in the country, classified as a population center with regional services.

The rapid urbanization of Tijuana can be attributed mainly to its border location, making it a strategic reception point for migrants. The city has grown to become a dynamic and ever-evolving metropolis.

It's estimated that over 19 million tourists cross the border in Tijuana each year, averaging more than 50,000 visitors per day, driving more than 10,000 vehicles. Additionally, there's a floating or semi-floating population consisting of a large number of compatriots who live in the city temporarily, either trying to cross into the United States or returning to their homeland.

Recently, Tijuana has become an important hub of development, with an estimated population of two million people, making it one of the top four cities in the country. Known for its predominantly family-oriented tourism, Tijuana is referred to as the "Grand Gateway to Mexico."