Even with no French, I can see that “In Search of Lost Time” is a more literal translation, but when did the English title get changed, by whom, and why?
There may actually be a really interesting story behind that, (if so, I’ve missed it), but the more probable explanation is more mundane: When books are translated and sold in other countries, the new publisher generally gets to assign the title. Some editor probably thought the title we have would sell better in the English-speaking world.
(The same thing can happen even without translations. Books released in the U.S. or the U.K. then published on the other side of the pond have new titles slapped on them by the publisher for “saleability” reasons every once in a while. For that matter, a book that the publisher likes that sells poorly may be re-published in the home country with a new title. Until an author has reached a sales level where s/he can dictate terms, they rarely have control over the title of their own work.)
The first translator applied the title Remembrance of Things Past, which I believe is a translation from Shakespeare. The title In Search of Lost Time is coming into vogue now, interestingly at about the same time as Anna Karenin and The Karamazov Brothers. No word yet on The Miserables or The Capital.
I mean, of course, a quotation from Shakespeare.
matt_mcl is correct. It’s from Sonnet 30.