|Fig 1: George Tierney, MP for Southwark, by William Nutter|
On Friday, May 25th, 1798, Pitt brought forward an emergency bill in the House of Commons to increase the supply of naval manpower in the war against France. The objective was to lift the existing exemptions from naval service which allowed men employed in the river and sea trades to evade military duty. The opposition MP and staunch Foxite George Tierney objected to the bill, calling for more time to consider it. In response, Pitt lashed out at Tierney's antipathy towards augmenting the navy, and stated that Tierney's reasoning for this might be accounted for as an attempt "to obstruct the defence of the country."  Tierney took umbrage with Pitt's accusation. He appealed to the Speaker (Henry Addington) that Pitt's language was "surely not parliamentary," and should be brought to order.  However, instead of interposing to mitigate the situation, the Speaker did not state whether he believed the language Pitt used was parliamentary or otherwise, and instead waited to hear Pitt's explanation.
Mr. Pitt refused to retract or explain what he had uttered before. In substance, Pitt said he "knew very well that it was unparliamentary to state the motives which actuated the opinions of Members, but it was impossible to go into arguments without sometimes hinting at the motives which influenced an opposition to it."  Nothing more was openly said in the House. The bill was read three times, sent to the House of Lords (who passed it the same day), and the following day it received the royal assent.  That, however, was far from the end of the confrontation. On the same night as the debate, May 25th, Tierney wrote to Pitt - challenging him to a duel:
"Hertford Street, Friday Night [25th May]
In the debate this Evening on your motion for leave to bring in a Bill for the Augmentation of the Navy you were pleased to declare that no man could deplore it in the manner I did unless it were from a wish to impede the defence of the Country. On being called to order you said something which savoured of Explanation, and with which it is not impossible but that, considering the latitude usually allowed in explaining Expressions made use of in the course of parliamentary discussions, I might have been persuaded to have been satisfied. Your Explanation however having afterwards been alluded to by another member, you thought proper in reply to say, "I gave no Explanation because I wished to abide by the words I had used." Upon this new and unprovoked Attack I withdrew from the House [which explains why the matter then dropped], and instantly committed to Paper the above offensive expression by which you chose deliberately and unwarrantably to repeat, & confirm your original Insult. Under these Circumstances whatever pain I may experience in being driven to call upon you in the manner I now do, it is a consolation to me to reflect that the part I am compelled to take is cast upon me by your own conduct. That you cannot justify the gross Imputation you ventured to throw upon me, & that without a total disregard to my feelings as a private & and my character as a public man it cannot be expected that I should submit to it. I know what is due to your particular Situation [Pitt was head of the government], but I also know and I trust you will recollect what a Gentleman, as wantonly provoked as I have been, has a right to require. Mr. Walpole [Tierney's second in the ensuing duel] also has the goodness to be the Bearer of this, [and] will communicate with any Friend [i.e. someone chosen by Pitt to be his second] you may be pleased to name for the purpose of privately arranging this Business. I am, Sir, Y[ou]r Obed[ient] Ser[van]t, George Tierney." 
Pitt received Tierney's challenge on Saturday May 26th, and he immediately accepted. Pitt then made the necessary arrangements. He wrote his will, and contacted Addington to inform him of the situation. Pitt initially wanted his close friend Thomas Steele, who was MP for Chichester and at that time Paymaster of the Forces, to be his 'second' in the duel. Finding Steele unavailable, Pitt then called on his friend Dudley Ryder, who was also joint Paymaster of the Forces at that time. Ryder served as Pitt's second, and Walpole acted in that capacity for Tierney. On the following day, Sunday May 27th, 1798 - the day before Pitt's 39th birthday - Pitt fought a mercifully bloodless duel with Tierney on a site where Wimbledon Common joins to Putney Heath.
Although the duel did not result in any injury or loss of life, a few days later Pitt was in his sickbed. He would not be seen publicly or in the Commons for weeks afterwards. 
1. Gifford, J. (1809) A history of the Political Life of the Right Honourable William Pitt, Vol. V. London: Cadell & Davies, p. 264.
3. Gifford, J. (1809) A history of the Political Life of the Right Honourable William Pitt, Vol. V. London: Cadell & Davies, pp. 266-7.
5. George Tierney to the Rt. Hon. William Pitt. Devon Record Office, Sidmouth MSS: 152M/C1798/OZ/11.
6. Hague, W. (2005) William Pitt the Younger. London: Harper Press, p. 427.
Fig 1: George Tierney by William Nutter, stipple engraving, published circa 1857. NPG D19248. George Tierney