Format
The language rule was brought back in this contest, four years after it had been dropped in 1973. However Germany and Belgium were allowed to sing in English, because they had already chosen the songs they were going to perform before the rule was reintroduced.
As noted in The Eurovision Song Contest - The Official History by author and historian John Kennedy O'Connor, the contest was originally planned to be held on 2 April 1977, but because of a strike of BBC cameramen and technicians, it had to be postponed for a month.
Read more about this topic: Eurovision Song Contest 1977