Possible Clues:

• Cade only half intended such bold resistance
• Lower classes intended resistance
• Heartlessly declare intended challenge
• Challenging attitude of French partner
• Insolence of French intended
• Obstreperous attitude from French groom-to-be
• To break an engagement, is that such a challenge?
• Rebellion of French chap about to get married
• Having got fed up with such a nice mix-up, one may put an end to one's engagement
• Beak the engagements, perhaps, by way of a challenge