TWENTY years ago this month a musician died who affected the lives of people across the globe.

He sold tens of millions of albums worldwide but never had, far less wanted, a hit single, appearing regularly on the Old Grey Whistle Test but never on Top of the Pops.

He turned down an invitation to join the Rolling Stones. His response to demands for encores delayed Jethro Tull getting on stage at the Isle of Wight Festival in 1970.

When he caught a post-operative infection following a liver transplant he left neither wife nor children but a great many orphans who felt a deep loss. Some of them, inspired by his playing, had gone on to great success in their own right - Brian May of Queen, Johnny Marr of The Smiths, Slash of Guns N' Roses, The Edge of U2 and James Dean Bradfield of the Manic Street Preachers among them.

In spite of the adulation of his peers, Rory Gallagher spent his life wracked by self-doubt, his health wrecked by a mixture of prescribed tranquilisers and alcohol.

Shy offstage and with a wholly inappropriate modesty about his talent, when he plugged in his battered Fender Stratocaster he was a man transformed, a driven, charismatic workaholic who rewarded the enthusiasm of his fans with gruelling, sweat-drenched performances that lasted more than three hours.

Everybody went home exhausted and happy, everyone that is except for Rory who went back to his melancholy and introspection. His death at 47 released him from his demons, but left the rest of us bereft because if there is any genre that allows musicians to mellow and play on into old age it is the blues.

I could listen to Gallagher all day. I mean that literally. My iTunes library contains 276 songs across 27 albums that would play for a shade under 23 hours.

Once a year I get to go one better and listen to his work, and other similar material from the blues rock genre, for four days in the small town in County Donegal where he was born, at Rock Hospital, Ballyshannon, in 1948 while his father was working on building a hydro-electric scheme there.

A friend and I saw Gallagher's first band, Taste in the late 1960s and after that power trio split Gallagher fronted his own band through the seventies and eighties.

There was always a feeling of connection, of shared experience, a sense of never being short-changed, and yet an impressions that he was, in the words of the lyric from his song Shadow Play, "a little Dr Jekyll, a little Mr Hyde" as someone so quiet offstage became a monster on it, driving his band on relentlessly.

Twelve years ago we heard of the tribute festival in his hometown and travelled over for it, and we've returned almost every year since. Those first years saw us visiting the Celtic Tiger, a booming economy with ambitious building projects, although our first stays were in an odd little business, a bed and breakfast to the front but with an undertakers at the rear.

We now have an circle of friends from Ireland, Scotland, England and across Europe who we see for one weekend a year, as this town of 2,500 locals hosts up to 15,000 incomers. The banking crash and recession have hit, very visibly, and while there may be a recovery under way in Dublin, there is not much sense of that reaching this corner of Donegal.

One publican told us that many establishments make up to 60 per cent of their year's takings in this one weekend and, because of the 20th anniversary of Gallagher's death, it was as busy as ever. He once wrote a mandolin song called Going to My Hometown, and his hometown has much to thank him for.

Last weekend saw 30 acts play on 15 stages, from pubs and outdoor platforms to a special big top hosting many of those who played in Gallagher's line-ups over the years.

There was also an appearance by Wilko Johnson, successfully treated for what had been diagnosed as terminal pancreatic cancer. Some of you will know him from his role as the evil executioner in Game of Thrones. For the rest of us he was the driving force behind Dr Feelgood in the 1970s.

But the main thing this year, as always, was Rory Gallagher and his legacy. With teenagers not yet born when he died, singing along word perfect to his songs, it is clear his influence goes on.