Letter formulas

[Waterwolf]

How did we arrive at the convention of pairing 'Dear Sir/Madam' with 'Yours faithfully' and 'Dear [name]' with 'Yours sincerely'?

[Quizmonster]

A letter received by the diarist, Samuel Pepys, in 1702 had the subscription: "Your most sincerely obedient servant". "Yours sincerely" did not appear, as such, until after 1800.

William Pitt, in 1797, wrote this subscription to a letter: "Most sincerely and faithfully yours", which combines both words.

Even today, many writers of letters to 'The Times' still sign off with the "obedient servant" approach!

My guess is that the different 'sincerely/faithfully/obedient' approaches developed during the Victorian age, as industry and education expanded, requiring different approaches to one's correspondents. Prior to that, most letter-writing was done by the upper classes who had no need to distinguish between them.