Elopement's in Jane Austen's world
Elopements were quite scandalous in Jane Austen's time, and still are a little today.
There are two planned elopements in Pride and Prejudice, both involving Mr Wickham. He first plans an elopement with Georgiana Darcy for her fortune, hoping to marry her without her brother finding out until it was done, but Mr Darcy does find out and puts a stop to this. The second he promises Lydia Bennet that he will elope with her despite having no such plans to, and is then forced to marry her in order to save her reputation.
Eloping meant that a man did not have to ask for the father's permission. Not requesting permission was considered rude and went against societal politeness. For Wickham to elope with Lydia would have been illegal as at 16 she was not of age to marry without her parents permission. The legal marrying age without parental permission was 21.
The Marriage Act of 1753 also made it increasingly difficult for men and women to marry outside their rank. In cases such as these a couple could obtain a special license from the Archbishop of Canterbury if they were really wealthy, or elope to Gretna Green, which was the first easily reachable Scottish village, where the marriage laws differed from England and Wales.
If a couple did elope, it meant that they were unattended until they were married. Normally when a young couple courted they could not be left unchaperoned. If travelling far to elope, a couple would have to stay overnight somewhere, which suggests to everyone that the couple had a sexual relationship before marriage, which was quite scandalous!
This is predominantly why the Bennet sisters reputation is felt to be tarnished by association to Lydia and Mr Collins comments: "the death of your daughter would have been a blessing in comparison of this". Mary Bennet also comments: "Unhappy as the event must be for Lydia, we may draw from it this useful lesson: that loss of virtue in a female is irretrievable; that one false step involves her in endless ruin; that her reputation is no less brittle than it is beautiful; and that she cannot be too guarded in her behaviour towards the undeserving of the other sex". This is not to say that Pride and Prejudice is the only Jane Austen novel that contains an elopement. Following the scandal of her sister, Julia elopes with Mr Yates, and Colonel Brandon had intended to elope with his love Eliza in Sense and Sensibility.