1821: Mexico Declares Independence from Spain,
Opening Port Trading
The Spanish were the first western European explorers to settle the land that is now San Francisco. However, when Mexico declared its independence from Spain in 1821, San Francisco became a Mexican territory, which led to fewer trade regulations and increased secularization [23]. Open trading practices brought English and American seamen to the area, and several began to settle there—forming a community that came to be known as Yerba Buena [23]. These decreased regulations were critical to boosting maritime trade and commerce, which provided wealth for development beyond the existing presidio and mission. The years following 1821 transformed the early San Francisco settlement into a significant global port town.
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