Conservatories have evolved from glasshouses. The beginnings of the modern greenhouses were in Italy in the 13th century, when the problem occurred, how to grow tropical plants, which were brought by explorers. Records from the 15th century Korean Peninsula talk about greenhouses in which they maintained a comfortable temperature during the winter for growing mandarins. Progress in constructing greenhouses occurred in the 17th century, when quality of glass was improved and new methods of construction emerged.
In the 16th century European rich people started to build greenhouses for citrus fruits (lemons, oranges, mandarins). They were massively building so called orangeries. Orangeries were greenhouses for growing oranges. They were built out of wood, stone and brick. South walls had high vertical glass windows. Orangeries were not intended only for growing oranges, but also for social activities like drinking afternoon tea and other parties.
Progress in the manufacture of glass in the 18th century encouraged the construction of greenhouses, orangeries and predecessors of conservatories. In England and the Netherlands were built greenhouses some of which are still architectural wonders today.
Lack of raw materials due to the first and second world war stopped the development of conservatories and other glass houses. Only with technological advances and development of lightweight construction materials and insulated windows in the 70ies of the 20th century began the development of modern conservatories. With the development costs of installation and maintenance were reduced.