Amadeo Peter Giannini (1870-1949), born in San Jose, California, was the founder of the Bank of America.

Giannini's parents were Italian immigrants to the United States. Giannini opened the Bank of Italy in a former San Francisco, California saloon on 17 October, 1904. Deposits on that first day totaled $8,780. An early difficulty to overcome was the San Francisco earthquake of 1906. Giannini was forced to run his bank from a plank across two barrels in the street for a time.

By 1916 Giannini had expanded and opened several other branches. It became the Bank of America in 1928 and continued under Giannini's chairmanship until his retirement in 1945. Prior to Giannini's creation of the Bank of America network, most banks were limited to a single city or region. By expanding to many regions, Giannini created a banking network that was able to easily handle local economic crises.

Giannini is credited as the inventor of many modern banking practices. Most notably, Giannini was one of the first bankers to offer banking services to middle class Americans, rather than simply the upper class.