It was one of those delightful experiences the other evening when I turned up at the City Halls in Glasgow to hear Edvard Grieg's Piano Concerto, brought to us by the BBC Scottish Symphony Orchestra, with Lars Vogt at the piano.

The large audience joined in the most rapturous response to a performance that surely raises the question: has there ever been a richer melody than this? It was Tchaikovsky who was moved to say of his fellow composer: "What warmth and passion there is in his melodic phrases; what teeming vitality in his harmony. If we add to this that rarest of qualities, a perfect simplicity, far removed from affectation and pretence, it is not surprising that everyone should delight in Grieg."

Yet, as I looked around the entranced faces in that audience, I wondered how many of them knew that Norway's national composer was as much one of us as one of them. For a start, his family name was not Grieg but Greig. And for generations those same Greigs had farmed at Mosstown of Cairnbulg, near Fraserburgh in Aberdeenshire.

It was from there, by chance, that Alexander Greig accepted an invitation from a fellowAberdonian to cross the sea to Norway and work in the British Consul's office in Bergen. In time, Alexander became the consul, to be followed by his son and his grandson, who was the father of Edvard.

Through all those years the Greigs, keeping up their Scottish connection, crossed the North Sea to Fraserburgh twice a year in a small boat to attend communion in the local church. Can you imagine it today? While there, they were able to pay homage to the vast array of relatives who lie buried in the area to this day.

By now, they had transposed the two vowels in their name, apparently because, by continental practice, they were being called "Grige", a pronunciation they disliked. Thus we came to the more melodious sound of Edvard Grieg.

And hereabouts I should perhaps declare an interest. While Edvard became steeped in the folk-music of Norway, my own great-grandfather, Gavin Greig, was similarly engaged with the folk songs of Scotland (well aware of his family roots, Grieg acknowledged the similarity of the two traditions).

What's more, in delving into his own family background, Gavin Greig was said to have traced his roots to that same farm of Mosstown, near Fraserburgh. The two men were both born in the middle of the 19th century and my grandmother, Gavin's eldest child, told me of her father leaving by train for Edinburgh to attend a piano recital by Edvard. But in those more respectful days he refrained from going backstage to introduce himself to his distant cousin. What a meeting that could have been.

As a distinguished headmaster in the Buchan district of Aberdeenshire, Gavin Greig became better known nationally as a novelist, poet, playwright and, yes, as a composer. At least one of his musical plays, "Mains's Wooin'", has been performed in modern times.

But he gained most prominence of all when he was commissioned by the Spalding Society to save the vast range of folk song which had been handed down by word of mouth but never committed to paper. Enlisting the aid of his friend, James Duncan, he scoured the countryside year after year, finding and listening to the last witnesses of those songs and using his musical knowledge to put them on record, before they were lost forever.

The result was eight massive volumes, published by the University of Aberdeen and the School of Scottish Studies in Edinburgh, recognised to this day as a world-class achievement. All of this was drifting through my mind that evening as I listened to Grieg's masterpiece. As the swell of the music reached its glorious climax, the image of Greig and Grieg was vividly before me - and I must confess to a quiet tear.

In my recent autobiography I made much of the fact that music is the great consolation of life. I never knew that more clearly than during my walk home through the streets of Glasgow the other evening, the echoes of a wonderful experience still ringing in my head.

A Final Grain of Truth is published by Black and White Publishing