I know it's small consolation today, but it is worth remembering that today (23/4) is the anniversary of City winning the FA Cup in 1904. It was Manchester's first major trophy and led to huge celebrations in Manchester (the whole population turned out according to one report).
City also ended that season 2nd in the League - the highest a Manchester side had come at the time.
Of course it wasn't Manchester's first national honour - that came in 1899 when City won the Second Division title - but it was a key moment in creating Manchester's footballing identity. I'm writing about it for the 2013 FAC final programme (along with a piece on the 1999 play off semi final).