<P> The Bureau International des Expositions also recognises the Milan Triennial Exhibition of Decorative Arts and Modern Architecture, on grounds of historical precedence, provided that it retains its original features . </P> <P> World's fairs originated in the French tradition of national exhibitions, a tradition that culminated with the French Industrial Exposition of 1844 held in Paris . This fair was followed by other national exhibitions in continental Europe and the United Kingdom . </P> <P> The best - known' first World Expo' was held in The Crystal Palace in Hyde Park, London, United Kingdom, in 1851, under the title "Great Exhibition of the Works of Industry of All Nations". The Great Exhibition, as it is often called, was an idea of Prince Albert, Queen Victoria's husband, and is usually considered to be the first international exhibition of manufactured products . It influenced the development of several aspects of society, including art - and - design education, international trade and relations, and tourism . These events have resulted in a remarkable form of Prince Albert's life history, one that continues to be reflected in London architecture in a number of ways, including in the Albert Memorial later erected to the Prince . This expo was the most obvious precedent for the many international exhibitions, later called world's fairs, that have continued to be held to the present time . </P> <P> Since their inception in 1851, the character of world expositions has evolved . Three eras can be distinguished: the era of industrialization, the era of cultural exchange, and the era of nation branding . </P>

What was the primary purpose of world's fairs in the late 19th century