In my family, the name “Mrs. Grundy” was used to describe someone of rigidly conformative taste and judgement (and keenly censorious bent). I’d always assumed it was just a family notion or perhaps a Yorkshire-ism, but the Wikipedia entry makes it clear that Mrs. Grundy has been the bane of many a would-be adventurous or daring spirit for centuries:
Mrs Grundy is a figurative name for an extremely conventional or priggish person, a personification of the tyranny of conventional propriety. A tendency to be overly fearful of what the respectable might think is also referred to as grundyism.
Although she began life as a minor character in Thomas Morton’s play Speed the Plough (1798), Mrs Grundy was eventually so well established in the public imagination that Samuel Butler, in his novel Erewhon, could refer to her in the form of an anagram (as the goddess Ydgrun). As a figure of speech she can be found throughout European literature.
It also discusses a real-life Mrs. Grundy from the early nineteenth century:
During the reign of William IV (reigned 1830-1837) a Mrs Sarah Hannah Grundy (1 January 1804 – 30 December 1863) was employed as Deputy Housekeeper at Hampton Court Palace one of Henry VIII of England’s most famous residences. Her husband, John Grundy (1798/1799 – August 1861), was keeper of the State apartments. Mrs Grundy became Head Housekeeper on 22 April 1838, a year after Queen Victoria ascended to the throne, and she served in that position until 1863 when she retired. Her duties included the care of the chapel at Hampton Court.
Royal families stopped using Hampton Court as a residence in 1737, and from the 1760s onward, it was divided up for “grace-and-favour” residents who were granted rent-free accommodation in return for great service to the Crown or country. These private rooms numbered in the hundreds. Much is revealed about the Victorian ladies living at Hampton Court Palace through their letters, particularly their correspondence to the Lord Chamberlain’s Office as the Ladies attempted to get around the regulations — to exchange their apartments for better ones, to sub-let their apartments for profit, to keep dogs, or other matters of convenience. Equally revealing are the letters from the Housekeepers to the Lord Chamberlain, complaining about the Ladies’ behaviour.
However, a bit of Canadian history indicates that the use of the term “Mrs. Grundy” as I’m familiar with it long predated the lady who policed morals at Hampton Court:
… in a book published in 1836, The Backwoods of Canada Being Letters From The Wife Of An Emigrant Officer, Illustrative Of The Domestic Economy Of British America, by Catharine Parr Traill, she writes: “Now, we bush-settlers are more independent: we do what we like; we dress as we find most suitable and most convenient; we are totally without the fear of any Mr. or Mrs. Grundy; and having shaken off the trammels of Grundyism, we laugh at the absurdity of those who voluntarily forge afresh and hug their chains.” This appears to show that the modern concept of “Mrs. Grundy” was current before the Mrs. Grundy of Hampton Court began her reign.