What practical function did the heavy curtains on medieval four-poster beds serve?

Answer

Providing privacy and retaining heat in drafty, unheated stone homes

In medieval settings, domestic architecture was often drafty and lacked internal heating. Heavy curtains were added to four-poster beds to create a small, enclosed micro-climate that trapped body heat, keeping the sleeper warm during the night. Additionally, because beds were frequently placed in communal living areas rather than dedicated private rooms, these curtains were essential for establishing visual privacy from other household members.

What practical function did the heavy curtains on medieval four-poster beds serve?
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