is house of stuart a noble household?
No, royal house
House of Stuart
The House of Stuart, originally Stewart, was a royal house of Scotland, England, Ireland and later Great Britain. 
high official in the household of a medieval king Those were often filled by men of rank: sons of the lord's relatives, or his retainers. describe the households of nobles? Royal household officials were largely responsible for the governance of the realm, as well as the administration of the household. name a few noble households? Carolingians of France, who rose from the position of royal stewards – the Mayors of the Palace – to become kings in their own right.
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House of Stuart [SEP] Introduction
The House of Stuart, originally Stewart, was a royal house of Scotland, England, Ireland and later Great Britain. The family name itself comes from the office of High Steward of Scotland, which had been held by the family scion Walter fitz Alan (c. 1150). The name "Stewart" and variations had become established as a family name by the time of his grandson, Walter Stewart. The first monarch of the Stewart line was Robert II whose descendants were kings and queens of Scotland from 1371 until the union with England in 1707. Mary, Queen of Scots was brought up in France where she adopted the French spelling of the name, "Stuart".