venturing her all upon the die
The reference to a die is associated with a phrase attributed to Julius Caesar: iacta alea est. Caesar was supposed to have said “the die has been cast” upon crossing the Rubicon, a boundary marker for Italy, with his army. This was the beginning of a civil war which saw Caesar defeat his enemies and become dictator of Rome. Arabella, in attempting to become engaged to Lord Rufford is undertaking a very risky plan that may end very well or very badly, much like Caesar’s gambit in beginning a civil war. [CD 2012]
Source: Suetonius, Life of Julius Caesar 33.
fortune would have favoured her
This is a reference to a phrase found in Vergil’s Aeneid, where Turnus says audentes fortuna iuvat, “fortune aids the daring” Turnus is trying to persuade his peers to attack Aeneas, starting a war that would be deadly. Arabella is likewise daring or bold during her attempt to become engaged to Lord Rufford. At this moment, she finds herself with an open chair next to her at dinner, and the narrator states that if Lord Rufford came during meal, Arabella’s boldness would be rewarded. Rufford could then sit beside Arabella, and she could continue her courtship with him. [CD 2012]
Source: Vergil, Aeneid 10.284.