There is no record of the “first” curtains, but window shutters or blinds preceded curtains. Glass for windows did not appear in any great sense until the early 1600’s so that the primary concern was to provide protection rather than window decoration, and cloth was far more expensive than locally cut timber, which could be fashioned into a window cover.
By the mid 1600’s in the UK curtains made from expensive material were prime targets for thieves. For the rich, window curtains were an accessory to match the curtained bedsteads, as much as to block light, or provide privacy in the bedroom. Such was the exclusivity of having window curtains that an early 17th century inventory of items for sale from an estate listed the curtains separately, something we would not consider today. Choice of material revolved around ability to pay, as much as personal aesthetic preference.
Increasing wealth, particularly from merchant trading, bought satin and silk curtains into the realm of the middle classes. Rooms other than bedrooms now enjoyed the benefit of curtains, particularly the drawing room where entertaining took place.
The Industrial Revolution of the 18th and 19th centuries bought mechanisation to textile manufacturing and resultant lower costs and greater availability. The export of British woollen goods doubled in the first 70 years of the 18th century and meant that cheap fabric became available of many.
By Victorian times lace or net curtains were also used to dress windows and give more privacy from the people passing on the street outside. Many of these lace curtains were knitted or crocheted by the lady of the house.
So no matter which period your dolls house is set in a pair of curtains will help to add authenticity and charm to any room.