The flag is hugely significant to the city of Limerick as it was hoisted during the mobilisation of the volunteers in the city.
It was confiscated by the British troops. When soldiers from the Leinster regiment left Limerick they took the flag with them.
It has been in the Imperial War Museum in London since 1935.
The return comes after Councillor Maurice Quinlivan made inquiries which led to the museum agreeing to a long term loan – on condition that the flag is kept in a display case.
“There was no uprising in Limerick, but there was a mobilisation of volunteers in the city who made this tricolour. While the flag was in the Imperial War Museum, it was on loan to the museum from the Royal Collection, which is the property of the queen.
“A member of the Limerick City Museum staff here in Limerick told me about this very symbolic tricolour and I worked on trying to get it back. I contacted a number of Labour MPs in London who helped put through a request to the Imperial War Museum for the flag to be brought back to Limerick for next year’s 100th anniversary.
“I had put in place a campaign for the return of the flag, but this was not necessary as the museum in London were very helpful.
“They have agreed to give the flag back to us on a long-term loan, which effectively means we can have it as long as we want.
“To give us the flag back on loan, the Imperial War Museum had to get permission of the Royal Collection, which is owned by the queen. So she is the one giving us back the flag.
“The queen has come up trumps in getting the flag back. If she’d give us back the Six Counties now I’d be very happy with her.”
Next year sees the 100th anniversary of the 1916 Easter Rising, which was one of the key events in Irish history.
Seven leaders seized control of the General Post Office in Dublin and declared Ireland an independent state. The men paid with their lives but they changed public opinion in Ireland and set in motion the chain of events that led to the formation of the independent Republic of Ireland.