The satellite link-up was devised by the BBC, which took the idea to the European Broadcasting Union in 1966.
The project editor was BBC executive Aubrey Singer. Personalities, including Maria Callas and Pablo Picasso, from 19 nations performed in separate items from their respective countries.
The event, which lasted two-and-a-half hours, had the largest television audience to date.
No politicians or heads of state were allowed to take part in the broadcast, and no pre-recorded videotape or film was allowed. Around 10,000 technicians, producers and translators helped make the event happen; each country had its own announcers, with translators narrating where necessary.
National broadcasting companies from 14 countries provided material for the 125-minute programme, which was shown in black-and-white. The organizations involved were: Australia (ABC), Austria (ORF), Canada (CBC), Denmark (DZR), France (ORTF), Italy (RAI), Japan (NHK), Mexico (TS Mexicana), Spain (TVE), Sweden (SRT), Tunisia (RTT), United Kingdom (BBC), USA (NET) and West Germany (ARD), and the programme was also shown – without contributing their own content – in Belgium, Bulgaria, Finland, Ireland, Luxembourg, Monaco, the Netherlands, Norway, Portugal and Switzerland.
In the week before broadcast, seven Eastern bloc countries -- led by the Soviet Union -- pulled out, apparently in protest to the Western nations’ response to the Six Day War.
The Beatles’ day began at 2pm with a camera rehearsal in EMI’s Studio One. An outside broadcast van was situated in the studio car park, which relayed the signal around the world via the Intelsat I (Early Bird), Intelsat II (Lana Bird) and ATS-1 satellites.