"An Englishman, an Irishman and a Scotsman . . ."

It’s a form of joke in the U.K.
The nationalities involved may vary, though they are most usually restricted to those within the UK and Ireland, and the number of people involved is usually three
The punch line is usually based around the Irishman's stupidity, the Scotsman's meanness, or the Englishman's snobbishness.
The joke begins "An Englishman, an Irishman and a Scotsman..." and then places the three characters in a scenario. How each person in the joke reacts to the scenario is then explained, the final reaction being the punch line, playing up to the stereotype of that nationality. Generally speaking in mainland Britain the Irishman is usually portrayed as the butt of the joke.
Let’s go to watch some examples:
· A Scotsman, an Englishman and an Irishman were discussing the infidelity of their wives. "I think my wife is having an affair with an electrician", said the Englishman, "Because I found an electrician's toolbox under her bed last night." "I think my wife is having an affair with a plumber", said the Scotsman, "Because last night I found a plunger under her bed". "I think my wife is having an affair with a horse", said the Irishman, "Because last night I found a jockey under her bed."
· An Englishman, a Scotsman, and an Irishman walk into a bar. The Englishman has a sword, the Scotsman has an axe, and the Irishman has a bomb. The Englishman throws his sword out the window and leaves. On his way home, he finds a little boy crying. "Oh, what is the matter, poor child?" "A sword flew out of the sky and it landed on my father..." the boy sobs. The Englishman walks home. The Scotsman throws his axe out the window and walks home. On his way home, he finds a little girl crying. "Dear lass, what's the matter?" he asks. "An axe fell out of the sky and it landed on my brother..." The Scotsman walks home. The Irishman throws his bomb out the window and leaves. On his way home, he finds a little boy laughing hysterically. "What's so funny, lad?" he asks. "I went to the loo and my house blew up."
Have a good laugh!
Miquel