The Ward sisters seem tone deaf to the literary resonance of the play's title, but it tolls for us. Lovers Vows are inevitably about constancy that marriage vows can't match. The phrase 'at lovers vows, Jove laughs' is as old as fornication, already proverbial in Homer's time (The Odyssey 8.381 although, as the bard sung it, it is all the gods but Jove, who laughed; and marriage vows, not lovers vows, that were violated.) Mrs Inchbald probably took her title from Shakespeare (Romeo and Juliet 2.2.92).

In the 18th century newspapers before 1798, the phrase is used satirically to refer to peace treaties with France and all satire forgotten, to bewail betrayal in publications like Memoirs of a Scoundrel by 'an Injured Fair'. It is also used poetically, to describe the sounds that lovers make, which makes me wonder if Miss Austen intends us to understand something explict when Maria squeezed her leg around the palisade at Southerton. From 1798 until the turn of the century, occurrences of the phrase "Lover's Vows" in the newspapers refer unambiguously to Mrs Inchbald’s play.(1)

The play is translated from Das Kind der Liebe, by August von Kotzebue, now just a footnote person, librettist for Beethoven, factor in the rise of German nationalism. In 1790 he was the most popular of German playwrights, above even Goethe and Schiller. Conventional critics faulted his morality because he restored the characters of fallen women; Romantics, because his morality depended on societal mores and cannon laws and lacked internal consistency. He wrote this play in the same year as the French Revolution, just before his own trip to France, when Leopold II (a brother of Marie Antoinette) became Emperor of the Holy Roman Empire. At that time, the Emperor had little personal control over his vast, linguistically and culturally diverse, historically vexed empire; uncomfortably wedged as it was between the powerful, annex-prone empires of Austria, Prussia, Russia and France; splintered into small duchies and city states really controlled by local nobles and clergy. Leopold ruled two years, his realm harassed by Napoleon and History only after he died. While maps have not yielded me specific literature or historical events satirized in Das Kind der Liebe, the geographical significance of the names of the characters kept me looking. Anhalt was divided into four principalities and two smaller electorates at the time, and there had been ongoing legal arguments regarding succession of heirs from marriages to commoners (several earlier Princes of Anhalt had made clandestine marriages). The princes are often Fredericks: Frederick Augustus the elector-Prince of Anhalt-Zerbst, Fredrick Ferdinand (who joined the Prussian Army in the year the play was written and fought on the Rhine), Frederick Erdmann (who married his niece), Fredrick Albert (who died in a shooting incident).Anhalt-Kothen-Pless and Anhalt-Kothen-Plotzkau are separated from each other by the Mulde river (in the original, Count Cassel is Count Mulde). And while it was sometimes difficult to prove qualification to inherit an Anhalt title, it seems they could sometimes be purchased.
Kotzebue’s own account of his life at the time barely mentions this play, addressing instead the critics of his previous play Menschenhass und Reue (performed in England as 'The Stranger'), and his malicious satire Doktor Bahrdt mit der eisernen Stirn, written just after. Kotzebue was a political player as well as a playwright: appointed to the service of Alexander I of Russia, exiled to Siberia, fleeing to France, suspected as a spy, rising to minor nobility in Germany; we know (what he did not) that his political satires lead to his death. His popularity, on the other hand, seems to have derived more from melodrama, happy endings and appeals to popular prejudice, less from satirical wit or clever writing. Das Kind der Liebe was celebrated for its sentiment, not its satire.(2)

Mrs Inchbald wrote the first translation into English, but it is not a straight translation: like Kotzebue, she pandered to her audience, giving a veneer of English hypocrisy to the 'German' vices her audience paid to be shocked by, altering its satire instead. The brilliant success of Nelson's Navy in its battle with France on the Nile had to be included, Cassel in Frankfurt was better known to the English (Anhalt-Zerbst had also supplied soldiers to quell the revolution in America, but the Hessians lived nearer to the German territories of King George III), and "some compliments ... paid to a German lady which the audience applied to HER MAJESTY by applauding in the most enthusiastic manner." could do no material harm to the play. Basest of all base appeals to patriotism, the butler turned comic, moving to centre-stage to cast Rhyming Couplets in praise of Nelson's victory on the Nile in a prolouge and an epilouge printed in the newspapers.
The play was an immediate success. (Its companion piece A Day in Rome did not fair so well. "The first interview between the lovers was fatal to the piece;...and[the leading man] being very imperfect in the story, bad as it was, the audience already satiated with the sentiment of the play, lost all patience, and began a series of hissing and hooting, which lasted till the curtain dropt.")Still the show went on , 'A Trip Down the Nile' replaced 'A Day in Rome', and Lovers Vows was still opening in the provincial theatres, its dated satire lost in popular acclaim, even after Trafalgar.(3)

I think Jane Austen has added yet another layer of satire to the story, using the theatre at Mansfield Park as a parody of the theatre of English parliament, and its relationship to the London Theatres. Like the English Parliament, and the Patent theatres of London, Mansfield Park can be said to have a lower house (the parsonage) and an upper house, with actors from the one finding their way into the other.
In the Upper House of Parliament, in February 1812, Henry Richard Vassal-Fox, the third Lord Holland, had recruited Lord Byron to the Whig cause. Byron had gone home to his estate, about 4 miles from the real Mansfield, and had been appalled at the wretched working conditions of the stocking makers of his district, and of the use of the militia to police them,. He determined to oppose a bill that would have men hung rather than transported if found guilty of breaking the new wider frames that were the cause of their slavery and the property of their employers. On February 27th, Byron made his maiden speech in the Lords (he described it as "loud and fluent enough, perhaps a little theatrical"; Lord Holland's papers describe the delivery as too theatrical, and Byron as too sensitive to personal insult for political life, but it reads well). The bill was passed in spite of Byron’s opposition, and Byron was soon lured away from the futility of prose: his poem Childe Harolde made him a celebrity and Lord Holland invited him to Holland House, to meet Lady Holland, one of the great hostesses of London, and her very literary set.
Holland House had a long history of private theatricals (as well as a big house and a little house). During Cromwell’s time, when theatre was prohibited, its loyalist residents built their private theatre. Swift was no stranger here, nor Gay, Pope or Addison. King George III, as a young man, was said to have fallen in love with fifteen year old Lady Sarah Lennox when seeing her perform as Jane Shore (mistress of Edward IV) in a private theatrical there., Sheridan was so frequently a visitor as to have aquired his own room (his School for Scandal was based on the antics of Lady Melbourne and the Duchess of Devonshire, who were also frequent guests there). At Holland House, Byron first met the Prince Regent, and also Lady Caroline Ponsonby Lamb, the wife of fellow Whig MP and baronet, William Lamb and her cousin, Anne Isabella Milibanke. Lady Caroline's open pursuit of Byron scandalized London, her cousin shunned the poet in spite of his fame, and Byron found himself more involved in the fashionable whirl of the 'bon ton' than in the House of Lords. He notes that on July 1, when summoned to the divisions on the proposal by Lord Wellesley that Catholic Relief be considered again by a committee "I had been sent for in great haste to a ball, which I quitted, I confess, somewhat reluctantly, to emancipate five millions of people". His liking for balls at the time seems odd – he did not dance, as he had a club foot, and he anonymously sent to the papers a poem called The Waltz, satirising England as prostituted to Germanic corruption.
For the reopening of Sheridan's theatre in October 1812 (it had burnt to the ground the year before) the newspapers advertised a poetry competition. Lord Holland explains "Mr Whitbread somewhat incautiously advertised for a competition of addresses to be spoken at the opening, with a promise of £100 to the successful candidate, and of entire impartiality in the selection . We received many dozen copies of verses. One was worse than the other, and not one fit to be delivered. In this emergency, for it was no less, I applied to Lord Byron"
Byron retired to the spa town of Cheltenham when he wrote this poem (and The Waltz), prudently escaping London and the shunned poets, and being rejected himself by Miss Milibanke , on grounds of character. The bitterness the rejected addressees might have felt was mollified by the popularity of the Rejected addresses, (not their poems, but a clever parody of the leading poets of the day, including Byron, whose accepted address was generally regarded as not one of his best) . To embarrass him further, The Satirist, or Monthly Meteor borrowed the epigram "with horn-handled knife/ Slaughter a tender lamb as dead as mutton" (from Playhouse Musings by 'S.T.C') to embarrass Byron when he returned to London, giving scandalous details of a ball where 'Lady C.' had "took up a dessert-knife" having met Byron there for the first time since he had sent her a cold letter informing her she was rejected for another. ( Miss Millibanke may not have been the 'other' - he had been having an affair with Lady Caroline's friend Lady Oxford in Cheltenham). Lady Caroline's own version of the story: "He had made me swear I was never to waltz. Lady Heathcote said, 'Come, Lady Caroline, you must begin'; and I bitterly answered, 'Oh yes! I am in a merry humour'. I did so - but whispered to Lord Byron, 'I conclude I may waltz now?' and he answered sarcastically, 'With everybody in turn - you always did it better than any one. I shall have a pleasure in seeing you'. I did so - you may judge with what feelings. After this, feeling ill, I went into a small inner room where supper was prepared; Lord Byron and Lady Rancliffe entered after; seeing me, he said, 'I have been admiring your dexterity'. I clasped a knife, not intending anything. 'Do, my dear', he said. 'But if you mean to act a Roman's part, mind which way you strike with your knife - be it at your own heart, not mine - you have struck there already'. 'Byron!' I said, and ran away with the knife. I never stabbed myself. It is false. Lady Rancliffe and Tankerville screamed and said I would; people pulled to get it from me; I was terrified; my hand got cut, and the blood came over my gown. I know not what happened after - but this is the very truth. I never held my head up after - never could. It was in all the papers, and put not truly" (4)

There was another piece of political theatre in the news and the parliament at that time (ie 1812-1814). The Prince Regent had revived the so-called 'delicate investigation' into the private life of Princess Caroline, obliging his ministers to leak testimony from 1806 that she had borne a bastard child, to justify his refusal to let her see her daughter. (The parliament was more open to royal influence in those days). The Whig Reformer Henry Brougham defended the princess (he had lost his seat in parliament already, by standing as an abolitionist for the seat of Liverpool). I can't see so many links between this and MP as I do between the opening of Dury Lane and the MP theatre, but maybe the Prince's denial of his estranged wife and his locking up his daughter and attempting to marry her off to the Prince of Orange was a reason for choosing Lovers Vows. Jane Austen's satire of the Prince of Wales in Emma was subtle enough for me to miss, and her opinion of spendthrift theatre-loving heirs plain enough. The newspaper satires were direct. They took the Queens side, but without much respect for her - using the investigation as a way of portraying the Prince as a latterday Haephestus, expecting a serious verdict on his farcical entrapment of a wife who had every reason to suppose her vows were only nominal.(5)

(1)In the Burney Collection of 18th century British newspapers, the occurrences of the phrase "Lovers Vows" prior to Mrs Inchbald's work are fairly equally divided between satire, poetry and indignation.
For a satirical example - St James Chronicle Thursday 18th of January 1781, Issue 3130, letter to the editor by 'Dormitor' (who I suspect might be Dr Samuel Johnson)
For a poetical example - Whitehall English Post Saturday 7th of June 1766, Issue 3134, Fidelia
Advertisement for Memoirs of a Scoundrel: Public Advertiser Friday 14th of April 1768, Issue 10439.

(2)August Von Kotzebue,Das Kind der Liebe
Robert L. Kahn, 'Kotzebue's Treatment of Social Problems', Studies in Philology, Vol. 49, No.4 (Oct., 1952) pp. 631-642
George S. Williamson, 'What Killed August von Kontzebue? The Temptations of Virtue and the Political Theology of German Nationalism, 1789-1819',The Journal of Modern History, Vol.72, No.4 (Dec.,2000),pp. 890-943.
August von Kotzebue, Sketch of the life and literary career of Augustus von Kotzebue; with the Journal of his tour to Paris, at the close of the Year 1790, Written by Himself, Translated from the German by Anne Plumptre (H.D.Symonds:London, 1800)
August von Kotzebue, The most remarkable year in the life of Augustus von Kotzebue: containing an account of his exile into Siberia, and of the other extraordinary events which happened to him in Russia, Written by himself,translated by the Rev. Benjamin Beresford in Three Volumes (Richard Phillips: London, 1802)
Map of the area at the time
Brief description of the Holy Roman Empire
More detailed description of Holy Roman Empire and its rulers
1911 Encyclopaedia Britannica Entry on Leopold II
Explaination of the legal treatment of unequal marriage in the Holy Roman Empire, and its political consequences for Anhalt