This was the only Eurovision Song Contest where countries were permitted to submit two songs.
The voting was kept secret, and there was no scoreboard. Luxembourg did not send any jurors, asking the Swiss to vote on their behalf.
As of 2017, the only surviving video fragment of the inaugural Eurovision Song Contest is Lys Assia's reprise of "Refrain" following her victory for Switzerland. The audio, which was recorded from the radio broadcast is preserved almost complete, even though there's a missing portion of the interval act.
Michèle Arnaud (Luxembourg) and Lys Assia (Switzerland) were the only performers to sing both entries for their respective countries.
Austria and Denmark were to have participated in the 1956 Contest, but both countries missed the submission deadline. It was believed for years that the United Kingdom also missed the deadline, but in mid 2010s it was revealed that the UK never had the intention of participating in 1956. In fact, they tried to establish their own British music competition to rivalize with Eurovision. This competition would end up being the base for their national final in their first participations from 1957 onward. It was from this British format where the European Broadcasting Union took the idea of revealing the votes live with a scoreboard.