PS A lovely musical and informative link to the opera is presented here:

Bertolt Brecht's 'The Threepenny Opera' play from 1928  tells how Mr Peachum had a daughter who has gone behind his back to marry an extremely unsuitable 'suitor.' This bridegroom turns out to be a vicious city gangster, so notorious that he has earned the nickname 'Mack The Knife.' He is set upon revenge on Macheath who wonders 'should he stay or should he go?'

The play is said to have been based on 'The Beggar's Opera' which opened in London in 1728. At the end of 1928 Brecht was asked to write a play to open a new theatre by berliner Josef Aufricht and he settled on The Beggar's Opera to be reworked and renamed as The Threepenny Opera. He asked Kurt Weill to write the score. Ironically one of the most loved and memorable pieces 'Mack the Knife' was only hurriedly added at the end of the writing with just days to go!

Bertolt Brecht's "The Threepenny Opera" was written in 1928.

The timing of the writing of the play is important because of its historical context.

Brecht was writing in Germany between World War I and World War II.  During this time, Germany was experiencing serious social problems.  It had lost WWI and had been forced to pay large sums of money to the winning powers.

These reparations had damaged Germany's economy tremendously and had helped create a sense of chaos in German society.  Adding to this was the fact that Germany had been stripped of its colonies and its military power.

So Germany was a newly-poor and newly-weak country.  This made for tremendous social chaos.  Brecht's play is a manifestation of this chaos.