Demand for Irish passports soared this year to a new record high.
Despite speculation that the Brexit vote would drive unprecedented demand for Irish identity papers in the UK, the Department of Foreign Affairs said Britain's split from Europe was only one factor.
In total 740,000 passports were sought in the year to December 21.
Some 65,136 of those were from citizens in Northern Ireland and another 59,377 from people in Britain with Irish roots.
Foreign Affairs Minister Charlie Flanagan said: "It's been a very busy and challenging year for the passport office, but I'm pleased to say that they've met all challenges presented to them.
"There was increased demand for a variety of reasons - the Euros, the Olympics and I acknowledge that Brexit may have played a significant role.
"I do stress, however, that we don't know for certain, as we don't ask people why they want a passport, merely whether or not they're eligible for one."
Brexit was widely seen as a driver of demand in the weeks and months after the June referendum with the number of new applicants in that time up 17,300 compared to the same period in 2015.
Other statistics show significant fluctuations at different times in other years.
The passport office's figures for 2016 showed that May was the busiest month as 96,356 applications came in. T here were also surges in August, October and November.
Anyone born on the island of Ireland or whose parents are Irish automatically qualifies for citizenship.
In some cases, those who have an Irish grandparent can also apply - known in some quarters as the Cascarino effect after Jack Charlton's exploits as manager of the Republic of Ireland football team in the late 1980s and early 1990s.
One in four people in Britain is said to have Irish heritage.
Diplomatic staff in Dublin were forced to issue an appeal for calm in the days following the Brexit vote after post offices ran out of Irish passport application forms because of an initial surge.
The Department of Foreign Affairs also said the introduction of a passport sized card this year, accepted in 31 countries, was also a big success with 25,000 people now carrying them.
But Mr Flanagan said: "One anomaly is that some 75% of the take up for the passport card is male.
"So we'd like to see more women, and more people in general availing of that. Finally, our DFA travel wise app has also been a huge success - downloaded by nearly 10000 people."