Michael Browne met the Queen on the final day of the momentous state visit as she toured the majestic Rock of Cashel, imposing ancient ruins perched on a hill on the outskirts of the Co Tipperary town.
Mr Browne, mayor of Cashel, was one of several local dignitaries invited to the event.
He claimed it was his civic duty as the town’s first citizen to make the gesture.
“I just shook hands with her,” he said. “I just said to her ‘welcome to Cashel Your Majesty and I hope you enjoy your stay’. No more, no less.”
Mr Browne, who is in a wheelchair, said the Queen thanked him for his welcome.
As an invited guest, Buckingham Palace officials would have been aware that the two meeting was a strong possibility.
The handshake follows the Queen’s emotive expression of sympathy during the state dinner for those who suffered in centuries of strife between Britain and Ireland.
Asked if he was the first member of Sinn Féin to meet the Queen and shake hands, Mr Browne said: “I would say so, yeah.”
Sinn Féin president Gerry Adams earlier praised the Queen for her expression of sympathy and claimed he hoped the visit would pave the way for greater co-operation between the two countries.
Muiris O’Suilleabháin, Sinn Féin’s South Tipperary spokesman, said the party’s position remained that the visit was premature.
“Party members in Tipperary were surprised by Michael Browne’s action, especially as he recently signed a statement against the English Queen’s visit to the Rock of Cashel,” Mr O Suilleabháin said.
“Sinn Féin’s position on the visit of the English Queen to Ireland is that it is premature and we are opposed to it.”
The Rock of Cashel is surrounded on all sides by the Golden Vale and the site dominates the landscape.
It was the traditional seat of the kings of Munster for several hundred years before the Norman invasion in the 12th century and is said to be where St Patrick converted one of the monarchs in the 5th century.
A green state Bentley had been shipped from Britain for the visit and carried the Queen and Duke from the nearby helicopter landing site to the summit of the outcrop.
Spontaneous applause broke out from a group of invited guests and local dignitaries as the Queen, 85, and Duke, 89, walked into the site’s ruined cathedral.
The imposing former place of worship is without a roof and the Queen immediately recognised some of its features were gothic architecture.
When a choir from Cashel Community School began singing the Gaelic blessing, May The Road Rise To Meet You, their voices rose high up into the north transept were they stood.
The picturesque complex has a unique atmosphere and features an impressive 12th century round tower, 13th century gothic cathedral and 15th century castle.
The Queen created another milestone yesterday by becoming the first reigning monarch to visit the imposing site since her forebear Henry II.
Dr Eugene Keane of the Historical Properties Division at the Office of Public Works, took the Queen on a tour of the site.
Speaking about the importance of the visit he said: “It’s a new history for Cashel and we’re hoping it will deliver great benefits afterwards in terms of tourism.
Dr Keane added: “But historically the last time a monarch was here was in 1171 — Henry II. So it’s quite a gap in the meantime but to be here and experience it was just wonderful.”