For most people, the term "Victorian architecture" defines a diverse but singular style. The reality is that this term encompasses several architectural styles, all of which were used during the mid to late 19th century. The name, of course, comes from the reigning British queen at the time: Queen Victoria.
Victorian homeowners were very social; dinner parties took place several times a week and consisted of pre- and postmeal activities. For these socialites, having a home that was impressive and built in the latest style was key. (The ornate look was soon spurned, however, by the development of new construction technology, particularly the availability of affordable wood and the ability to incorporate steel into buildings.)
Although Victorian architecture is rooted in England, it quickly spread worldwide as British architects started to emigrate to Canada, Australia, New Zealand and the United States. Eventually, improved communications in the 19th century began to inform international architects of the latest and greatest styles and trends, and the Victorian influence grew.
Still, the exact Victorian time period and names of architectural styles differ from country to country. In the United States, Victorian style was generally popular from 1860 to 1900. San Francisco in particular is well known for its Victorian architecture. In Australia, the Victorian period was recognized from 1840 to 1890. Melbourne's world-heritage Royal Exhibition Building and Rialto Building are both good examples of classic Victorian architecture in Australia.