On what date did John A Costello informally declare the Irish Republic in Canada

Here is the run of events as I understand it. John A Costello was a barrister by profession and would have preffered the legal relationships to be cleaner than DeV's external association model which essentially was a Republic in all but name. The cabinet had discussed such a change but had not decided on it.

Read Elaine Byrnes piece

Historians have focused on the motivations for Costello’s Ottawa press conference where he announced his government’s intention to repeal the 1936 External Relations Act and declare Ireland a Republic. A leak to a Sunday newspaper and offence taken by Canadian protocol during the Governor General’s dinner in the taoiseach’s honour, are conventionally thought to have encouraged a rash response by Costello.



In his detailed, day-by-day account of the decision-making process which culminated in Ireland’s affirmation as a Republic, Costello’s private secretary, who accompanied him on his State visit to Canada, completely disregards this version of events.



Patrick Lynch would write that Costello “never acted on impulse”. The detail in Lynch’s testimony is such that he notes the number of journalists at the press conference (35) and the day’s temperature (95 degrees).




http://elaine.ie/?p=67

Roll on September and at a British Commonwealth meeting Costello endured some provocation as he saw it from the Governor General of Canada.

There was no interview with a newspaper but the Sunday Independent had run a story based on speculation that that was the case prior to the press conference.

There are several versions of events but this is the answer you are looking for.


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The Canadian Connection
Until 1948, under a piece of legislation known as the External Relations Act, the King of England played a peculiar role in what, seemingly, was an independent Ireland.
All ambassadors to Ireland were accredited to the Court of St James's in London. Costello's inter-party government decided to repeal the External Relations Act, and Mr. Costello made the announcement in Canada. The circumstances prompting the announcment to be made in Canada were as follows.
On September 1, 1948, the Taoiseach was a guest of the Canadian Bar Association in Montreal. His speech that day talked of "the inaccuracies and infirmities" attaching to the External Relations Act.
As Prime Minister he was hosted at official dinners over the next few days, both in Monteal and Ottawa. By design, or unintentional oversight, his hosts proposed only a toast to "The King". It was a diplomatic faux pas not to follow with a toast to "The President of Ireland".
It has since been claimed that the Taoiseach took personal umbrage at the slight. Be that as it may, it confirmed the need to free his country from the embarrassment of the External Relations Act, and on September 7, at a press conference held in Ottawa, Canada's capital, Mr. Costello confirmed that the act would be repealed, and in consequence thereof Ireland was dissassociating itself from what was then the British Commonwealth of Nations.



http://www.vindicator.ca/vindicator/erneFishery.html

DeValera had called Ireland a Republic several times at the end of WWII but the legal position was Dominion Status.

One area it affected was Irish Citizens travelling to Commonwealth Countries and on holidays years ago I was stung for visitors visa fees in some countries that British travellers did not have to pay

I think the subject has been covered by Talking History recently.

Some people including DeVs grandson Eamonn O'Cuiv have questioned the decision taken and Costello may have been presured by events and some speculate that the Sindo's story grew legs.