Art nouveau was a movement in the late nineteenth century that redefined the way people looked at art and architecture. It revolves around nature and ornamentation and there connection with art. During this movement, architects started integrating nature and natural forms into their works in every way, from the exterior structure down to the details of the interior. Art nouveau preceded modern architecture and it had a heavy influence on it. Three prominent figures who helped contribute to this influence on modern architecture were Victor Horta, Henry van de Vilde, and Hector Guimard. Art nouveau can be seen in several of their works, which would help contribute to the emergence of modern architecture.
Horta had very intimate feelings about nature. Natural forms can be seen in almost all of his works, in the exterior structure and the interior decoration. His designs were not always exact imitations of nature, but they were also simultaneous abstractions and integrated into the building as a whole. This is most prominent in his Tassel house, which contributed to the birth of modern architecture. In Horta’s Tassel house, he displays nature both literally and figuratively. The house contains palmiform columns that are highly abstracted, yet the winter garden contains actual palm trees.
One characteristic of Horta’s work was the he integrated spaces very well. He overlapped spaces to add an illusion of space. He was a progressive believer and in his Van Eetvelde house, he introduced a metal skeleton that supports a glass vault. The idea of the metal skeleton is seen in modern architecture. Through his glass vault he brought in natural light to animate form. Another progressive idea of his that is also seen in modern architecture is curved lines in the façade.
Artist Henry van de Vilde, who helped spark the art nouveau movement in Belgium, was an influential figure to Horta. Van de Vilde was the head of the decorative art movement, and gave a series of lectures that were inspirational to Horta. Vilde designed furniture that was so well integrated with the natural forms that the furniture seemed as though its style and shape was determined by its ornament. In Vilde design of the Maison du Peuple, the continuous glazing had a shocking effect. This helped contribute to the modernism movement. Also his Bloemenwerf house would become a prototype for villas in utopian colonies. 
Hector Guimard integrated decoration with architecture. Horta played an influential role to him, as Vilde did to Horta. Guimard was so impressed with Horta’s works, that he revised his drawings for his first large scale work. Also similar to Horta, Guimard integrated metal with plant form, even more so than Horta.
The ideas of these architects played a big role in the emergence of modern architecture. Curves started becoming prominent in Dutch architecture. In Barcelona, Lluis Montamer, who was the most important architect in early modernism, published an article stating the importance of nature in architecture. The upper class of Catalonia saw the emergence of modernism as a symbol of national progress. The Post Office Savings Bank in Vienna had functional glass with metal banking, similar to the works of Horta. The eventual decline of art nouveau and the rise of modernism can be attributed to the rise of machine production and mass society, which caused art nouveau to start to transform.
