<p>I think it depends of the rank of each servant, Mrs Hughes and Carson had their own room and even a "office", we must remember that being the butler and head housekeeper in a house like Downton was a big deal for a person who went to work in service.
</p><p>Add to that, we must remember the number of people working there, in the beggining it was full staff, after the war many people went to work to factories, offices, and the owners couldnt afford full staff. Many houses started to hire many people from the village, Chatsworth house. a country house that makes look Downton/Highclere like a cottage, had only 2 maids who sleep there in the 30´s, the majority of the staff were people of the surrounding village, the wifes and daughters of gardeners, farmers, etc.
</p><p>I think that when the series started William and Thomas shared a room, because they were footman, like when Alfred and Jimmy shared. Anna shared with Gwen, and with Ethel after. I think that when Anna was promoted to lady maid she was given her own room.
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