"In 1765 a young man wrote to the Court Miscellany, a British periodical, to ask whether he should fight a duel against a rogue who had insulted his beloved. The reply urged him to accept the challenge: “[F]or if you run your antagonist through the body, or he you, ’tis three to one but the other comes to be hang’d; and then there’s good riddance of two ridiculous hot-headed coxcombs.”"
Stolen from the Economist: "Agony aunts through the ages: Whatever should I do?"
/u/hazelnutcream provides a much more appropriate answer rather than my own anecdote, but I will leave this response as it is nonetheless, I think, an interesting bit of history.
Another will have to answer in regards to the history and changing perception of dueling, but I can say that certainly in Ireland it occurred without great outcry even well into the 19th Century. As I recount in much greater detail here, the Liberator - as he is known, Dónall Ó Conaill fought a famed duel against John Norcot d'Esterre in 1815; and there seemed to be no negative backlash from the event. To plagiarize my prior answer:
Ó Conaill had publicly called the Corporation 'beggarly', and d'Esterre - who was insolvent at the time - took personal offense and challenged him. D'Esterre was very much a member of the Protestant establishment, and a perfect villain (in the public mind) to oppose the enormously popular Ó Conaill.
Rather unfortunately for d'Esterre, who was extremely nervous about the whole thing and was probably strongly pressured into it, Ó Conaill was something of crack-shot, and wounded him in the groin during the duel - whereafter he died three days later in some misery.
There was quite a crowd for the duel, and Ó Conaill's killing of d'Esterre widely reported. Ó Conaill's already considerable reputation was buoyed by the victory (although not in Establishment circles one can imagine), and although he is reported to have been haunted by the outcome and paid an allowance to d'Esterre's daughter for the remainder of his life. Nevertheless he accepted a duel against the Irish Chief Secretary (and future Prime Minister of England) Robert Peel only a few months later, though the duel itself didn't occur... Doubtless any outcome would have significantly altered the course of history for both Nations. Peel's challenge of Ó Conaill perhaps speaks to the equivalent English social perception of dueling, though someone better versed in British culture of the period would have to confirm that.
^(Dáthí Ó hÓgáin. The Hero in Irish Folk History. Dublin, Ireland: Gill and MacMillan, 1985.)
^(Ríonach Uí Ógáin. Immortal Dan. Dublin, Ireland: Geography Publications, 1995.)
Robert Shoemaker argues that during the period 1660-1800, the violence of duels became more ritualized for an increasingly “polite” elite. The key point of a duel became a demonstration of courage, rather than a test of martial skill.
A shift from swords to pistols reduced fatalities by a factor of three fold. When gentlemen carried swords, a duel could take place immediately, but men rarely carried a set of pistols with them. The delay of the duel (often until the next morning) allowed participants to cool down, negotiate, sober up, etc. In addition, seconds stopped drawing their weapons at the same time as the principles and took on serious roles as negotiators to settle the dispute before the duel.
Pistols also largely removed the element of skill from duels. Gentlemen who practiced fencing had an immense advantage over unskilled opponents. However, it was considered poor form to practice with your pistol beforehand or intentionally aim the shot. As pistols became more accurate over the period, participants paced out longer distances.
James I passed statutes against dueling, but it became more popular after 1660. Participants could be arrested even for attempting to fight a duel, and therefore men tried to conduct duels at dawn or dusk outside cities to avoid attracting attention. Thief-takers (individuals hired to capture criminals before the advent of a professional police force) acted on tips to catch duelists. Ordinary people also attempted to subvert duels by prompting negotiations or merely showing up where the duel was to occur. Shoemaker argues while fistfights occurred between people of the lower sorts, duels were mostly confined to a subculture of military officers and the elite.
Donna Andrew notes that clergy attacked dueling in the seventeenth century, but their criticism did not catch on. As khegiobridge mentions, the particularly gory duel between Lord Mohun and the Duke of Hamilton in 1712 fueled public sentiment against dueling. In the early eighteenth century dueling was criticized on the grounds that dueling violated honor as defined by one’s virtue throughout life. These commentators also recognized the threat dueling posed to the state by undermining its authority. By the 1770s, these criticisms sharpened around the idea of dueling as a feudal hangover that opposed the Law. By the 1790s, rising middle class of evangelicals increasingly criticized dueling. In the 1840s, changes to the legal process and laws meant that the court became an increasingly tempting solution for men to settle disputes. The incidence of duels dropped off sharply after 1842, and the last duel on record occurred in 1852.
Edited to reflect that the post on the Mohun-Hamilton duel is gone from the thread now.