Journalists not well versed on the history of Clannad have made the mistake of assuming the acclaimed Irish quartet became an overnight sensation with “The Theme From Harry’s Game” in 1992.

The thought amuses singer-harpist Maire Brennan.

First off, Clannad was formed in 1970 when Brennan, brother Ciaran and uncles Noel and Padraig Duggan took their traditional Irish songs from the stage of the Brennan family pub in Donegal and entered the Letterkenny Folk Festival. They won, and first prize was a recording contract with Philips.

They have since recorded countless albums, some in their native Gaelic and others in English. Their breakthrough came in 1982 when they were commissioned to write original music for a three-part TV movie in Britain. The song title: “The Theme From Harry’s Game.”

Fast-forward 10 years and the same song appeared on the “Patriot Games” soundtrack, became an instant hit on VH1 and fueled gold-plated sales for Clannad’s “Anam” and “Banba” albums.

Some overnight sensation.

“What’s really funny is that when ‘Harry’s Game’ happened again,” Maire Brennan said recently from her Dublin home, “people would say, ‘Oh, you must be influenced by Enya.’ Uh, sorry, but ‘Harry’s Game’ was 14 years ago, and they didn’t realize she’s my sister and that she was part of the group in the early ’80s.

“After finding that out, journalists who may have come in with three pages of questions have to start all over again.”

That’s fine with Brennan; Clannad has defied the odds for 26 years. Their latest Atlantic Records album, “Lore,” is No. 1 on Billboard’s world music chart. Produced by Hugh Padgham (Genesis, The Police, XTC) and Ciaran Brennan, “Lore” finds the group continuing a decades-long journey of fusing traditional elements with modern sounds.

” ‘Lore’ is related to storytelling or proverbs or anything that comes the cultural background,” Maire Brennan said. “We never know what we’re going to end up with when we go into the studio. There were a lot of songs when we went in, some songs that didn’t happen, and we were very picky about what went on the album.

“It ended up that there were five full Gaelic songs and some Gaelic in choruses on the other tracks. I think it proves that we are comfortable with Gaelic. That’s what we went for, what we really felt was close to us.”

Non-Irish listeners may not understand Clannad’s lyrics, but they are attracted to the group’s beautiful, ethereal melodies.

“We get letters from fans who just want to relate to us how much the music means to them and how it benefits their life,” Brennan said. “They tell us there’s a lot of soul and spiritual feeling in it. It’s extraordinary. I think it’s great that we’re doing something we love, that we’re always experimenting with sounds and that it’s keeping our interest in it. Hence, that’s probably why we’re still together after all these years.”