TWENTY years ago, as a tiny Irish village in south Tipperary celebrated the pilgrimage of one more US president to his ancestral roots, the people of Paisley had every reason to observe the hoopla intently.

Although it was little known at the time, Ronald Reagan belonged as much to Buddie-land as he did to Ballyporeen.

Acting exclusively for this newspaper, then known as the Glasgow Herald, Hugh Peskett, director of research at Burke's Peerage, discovered the late president's maternal great-great-grandparents, Claude Wilson and Margaret Downey, had been married at Paisley High Church on May 23, 1807.

The marriage register gave no details of occupation, but both parties were ''of the parish'' and Mr Reagan's personal family records reveal they and their children left Scotland for Illinois in 1832.

John Wilson, the former president's great-grandfather, was born ''somewhere in Renfrewshire'' on February 9, 1812. He married Jane Blue, the daughter of Donald (or Daniel) Blue and Catherine MacFarlane, from Kintyre, Argyll, and later Nova Scotia. American documents indicated John Wilson's son, Thomas, was also born in Scotland in 1843, an unusual fact because his parents must have returned from the States at a time when most who emigrated never saw their native shores again.

The first detailed census in Britain was in 1851 and, in Scotland, the general registration of births, marriages, and deaths began in 1855. A major improvement in US records did not occur until 1900 by which time Thomas, Mr Reagan's grandfather, had died.

The Wilsons named their Illinois farm Clyde and President Reagan, in response to the confirmed information from The Herald about his ''Scottishness'', recalled Clyde was also the middle name of his mother, Nellie Wilson. She had wed John Edward Reagan in Fulton in 1904. His family had arrived in Illinois, from Ballyporeen in the mid-1850s, settling within 20 miles of the Paisley Wilsons.

In 1991 Ronald and Nancy visited the church in Paisley where Mr Reagan's great-great grandparents were married. They attended a banquet in their honour at the Duke of Atholl's Blair Castle in Perthshire, laid on by the Keepers of the Quaich, a society which promotes whisky.