Nostalgia has never felt so alive as when the Human League are in the house. The Sheffield chart androids are arguably unique in that they are both critically adored – their early records were at the cutting edge of post-Kraftwerk synth-pop – and also old-fashioned hit monsters.

It is very much in the latter incarnation that they come to Palmerstown House Estate, Naas for the Forever Young festival in July. There they will share a weekend bill with Holly Johnson, Midge Ure, Marc Almond, Kim Wilde and others. Their old mates Heaven 17 – who seceded from the original Human League and struck out on their own – will be there too. It’s going to be quite a party.

“We know a lot of those bands ,” says League singer Susan Ann Sulley. “We know Midge. We know Kim Wilde really well. We used to all meet on Top Of The Pops back in the day.”

Sulley and fellow vocalist Joanne Catherall joined the Human League in 1980, as the project teetered on collapse. With a tour booked and his band falling to pieces around him, songwriter Phil Oakey visited a Sheffield night club eager, possibly desperate, to recruit a female backing vocalist.

He found two – Sulley and Catherall. A few months later, they were all bunkered down at Genetic Studios in Berkshire recording the League’s third long-player, Dare. With lead single ‘Don’t You Want Me’ doing to the charts what Daenerys Targaryen did to King’s Landing, the LP made stars of this unlikely alliance between a brooding songwriter and two relatively carefree and, by their own admission, naive 17 year-olds. All these decades later, Sulley remains faintly astonished at how it unfolded.

“It was a huge surprise,” she says. “None of us thought it would take off as quickly or as successfuly as it did. As a 17 year-old schoolgirl from Sheffield, that was quite hard to deal with at first. To this day I don’t understand how people can enjoy being in the public eye.”

With Dare a smash, the pressure was on for the trio to maintain their position at pop’s top table.

“It was really hard in the ’80s,” says Sulley. “There was a lot of expectation on us to be successful. Whereas now we can be anonymous – we can go out and no one will take any notice.”

She takes huge pride in the fact Human League aren’t simply a pop act (not that there’s anything wrong with simply being a pop act).

“We do care,” she says. “A lot of effort has gone into the music and the songwriting. The toil Philip has had go to through writing those songs. We see it in the studio. It’s nice that people appreciate it and that musicians in other groups have acknowledged us as an influence.”

That said, when they come to Naas in July they will know exactly why they are there. And it isn’t to bring fans up to date on their more obscure songs. So, yes, they will be playing ‘Don’t You Want Me’. And no, they probably won’t dust down anything from their late ’70s incarnation as the missing link between Throbbing Gristle, Joy Division and a drum machine on the brink of self-awareness.

“In a festival situation I don’t understand the point of not playing the hits,” nods Sulley. “You give the fans what you feel they want. There is categorically no point playing something from an album they’ve never heard of. You want them to have a good time – to go away and think, ‘wow, I don’t realise they had so many hits… how great was that show?’”

As with all long-running musical endeavours, they’ve obviously had their ups and downs. The 2000s were particularly testing with their albums Secrets (2001) and Credo (2011) failing to register with the public despite positive reviews.

“One reason we’ve managed to keep going is that we all have separate lives,” say Sulley. “When you’re in a group and are at work it’s very intense. You’re together constantly. The only time you are apart is when you’ve a day off and you’re in a hotel room on your own. It’s nice to get back to Sheffield and say good bye to everyone and go and do your own thing.” Another factor is the sheer diversity of their hit parade, she believes.

“We did Dare and, after that, ‘Mirrorman’ and ‘(Keep Feeling) Fascination’ – and each was very different from the other. And then we went to America and did Crash with [r & b production team] Jam and Lewis and came back sounding like an American soul band. Diversity is good. By trying so many different things, we worked out what we were good at.” Meanwhile, their audience has grown with them – ensuring the Human League will receive a heatfelt reception when taking to the stage at Kildare. “In our heyday people bought physical copies of records. They went out and spent their hard-earned money. And they played those songs over and over and they stuck in their heads. We are now reaping the benefits of that. Those people have had their children, they’ve paid their mortgages – and they’re thinking, ‘let’s go and see the Human League.’”

• The Human League play Forever Young, Palmerstown House Estate, Naas July 5–7