Written and directed by 22-year-old Alex Bates, the film follows how a local woman coped after the bombing of the tomato trucks on the White Rock at the start of the Second World War.
Beau Sejour theatre was packed with more than 300 people for the event and among the audience were islanders of all ages, as well as deputies, Bailiff Richard McMahon and Lt-Governor Vice Admiral Sir Ian Corder.
It was Mr Bates’ first production since finishing film school.
‘I originally thought it would a low-key film, but it just snowballed into something bigger than I ever imagined,’ he said.
More than 100 people were involved in the film's development and production.
Filming took place around Guernsey earlier this year and editing was completed just three days before the premiere.
‘I’m really pleased with it and really proud,’ Mr Bates said.
The audience gave thunderous applause after the 20-minute film finished.
People then had a chance to ask questions of the cast and crew before Kiya Ashton sang Sarnia Cherie – the film’s theme song.
Sir Ian said he had really enjoyed the film.
‘It was hugely impressive,’ he said.
‘If that is what young people are producing, then goodness knows what we will see in 10 years.
‘It makes me very optimistic for the future.’
He added that it was also a good way to introduce young people to the story of the tomato truck bombing and the impact it had on islanders.
Mr Bates is already looking to his next project, which will focus on obsession and toxic masculinity.
He plans to film it in Guernsey later this year.
‘I wanted to do something completely different next,’ he said.
As for Occupied, it will now have a series of screenings at the Mallard Cinema and Mr Bates plans to also submit it to film festivals. Later in the year it will be made available online.