The Origin Of "It's A Knockout".

The format known as It's A Knockout came about after a number of other shows were adapted and re-produced.  Top Town, an inter town BBC radio & television talent series from the mid 50's generated into Campanile Sera an Italian inter-town games competition in the late 50's. 

In 1962 this transpired to a French show called “Interville” (Intercity) devised by Guy Lux, Pierre Brive and Claude Savarit.  Two teams from different towns competed against each other in a games format against the clock. The inter European concept was thought up by French premier Charles de Gaulle who wanted something to bring countries together and increase the friendliness between them.

This international version Jeux Sans Frontières (translated to Games Without Frontiers or Games Without Borders) started in 1965 and was organised by the EBU (European Broadcasting Union or L'Union Européenne de Radio-Télévision "UER"). The BBC joined the European competition in 1967.

Intervilles is still televised in France on Channel 3 (the bottom right image from the 2007 series).