In short: Edwardian architectural style is defined clearly below. The Victorian architectural style includes varied styles and not something specific.
San Francisco's architectural styles have always reflected the fashions of the current historical period. Architectural style is a simple way of classifying buildings of a particular period according to these common design characteristics. San Francisco is famous for its Victorian buildings, but there is really no single Victorian architectural style. Queen Victoria lived from 1837 to 1901, and anything built during her reign is considered Victorian. Many varied and interesting styles emerged and were adapted and reshaped for American tastes in rapidly growing cities like San Francisco.
Edwardian is the named given to some homes built when Kind Edward VII was on the throne, just before the beginning of the first World War. The homes of the era were built at a time of economic stability and might include prominent roofs with false gables, bay windows, stained glass and Art Nouveau-influenced details. Edwardians combined elements of European Modernism and English Arts and Crafts styles but on a more expansive scale.
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