The stealing of Miss Belle Fermor's hair, was taken too seriously, and caused an estrangement between the two families, though they had lived so long in great friendship before. A common acquaintance and well-wisher to both, desired me to write a poem to make a jest of it, and laugh them together again. It was with this view that I wrote the Rape of the Lock.The incident behind the poem has never been authoritatively tracked down to place and time. It is improbable, but possible, that it happened, as the poem states, at Hampton Court; and the counter-claims of the houses of the Fermors, Petres, or Carylls have never been substantiated." (Twickenham, Vol II, p. 83)
Was Belinda, as the poem hints, willing to marry the Baron?
"Arabella may well have been considered as the possible bride for
Lord Petre. The rape of the lock may well have been an incident in the
period of circumspection--how thorough such circumspection was likely to
be may be gathered from the correspondence of Caryll during 1710-11 when
he was choosing a wife for his son. If two such families who 'had lived
so long in friendship before' are estranged through a fairly trivial
incident, it seems there is thunder in the air. All the fun of the poem
read very differently when, less than two months before the poem was
published, Lord Petre married Catherine Warmsley, a Lancashire heiress
some seven or more years younger than Arabella and much richer."
(Twickenham 93)
By the time Pope revised the poem in 1717, Lord Petre had died (of smallpox) and Arabella was married. Whatever the original purpose of the poem may have been, by the time Pope finished revising The Rape of the Lock the feud between the families was no longer particularly relevant.