Irish shares ended higher as banks that had suffered badly tapped into a very late-year rally in Europe.
At the end of a bizarre week in which US stock markets slid and surged and fell again in successive sessions, the Iseq Overall Index closed 2.2% higher.
That helped lift the Iseq from its 12-month low which it had hit earlier in the week, but the index has nonetheless lost 24% of its value from its year high, in late January.
All major European stock markets rallied. Frankfurt's Dax and the Cac in Paris rose by 1.7%, while the Ftse-100 in London was up by almost 2.3%.
"European markets have enjoyed a strong day, but on Wall Street the final day of this shortened week has begun with some losses after the surge into the close [on Wednesday]," said Chris Beauchamp, chief market analyst at online broker IG. But Mr Beauchamp again said that the week's rollercoaster in the US could point to trouble.
"The bounce of the past few days has taken place while the economic and macro backdrop remains frozen, with little movement on the trade wars, Brexit and now the [US] government shutdown debates that have been such drivers of sentiment and flows over the past year or more," he said.
Shares in Bank of Ireland and CRH, which had fallen earlier in the week, rallied strongly.
Bank of Ireland surged 2.4% but is facing into the new year having lost 31% of its value in 2018. It is now valued at under €5.3bn.
AIB shares gained slightly but they too have lost over 30% of their value this year. It is now valued by the market at under €9.8bn.
Among the other heavyweights, CRH rose over 3% to pare its losses for the year to 21%. Shares in the €18.8bn global building products firm have been hit by investors turning sour on growth stocks that rely on the US for a significant slice of their earnings.
A 1% gain for Kerry helped the international foods firm pare its losses in the past year to almost 7.5%. It's now valued by stock markets at almost €15.2bn.
Shares in Glanbia-- which expanded its operations in the US during the year--have gained 11% in 2018, to value it at over €4.8bn.