Such conferences have been a regular feature of Sinn Fein's engagement with the diaspora, but the latest event came at a particularly febrile moment in British-Irish relations.
That was underlined by the opening address from the party's new president Mary Lou McDonald, which called on the Irish Government and the EU to stand firm against a hard border on the island of Ireland.
A subsequent panel discussion featured some lively disagreement over the impact of Brexit on the terms of debate in Northern Ireland. Professor Peter Shirlow argued that the result of the post-Brexit Assembly election in 2017, which saw unionism lose its absolute majority for the first time, had been over-interpreted.
"It didn't change anybody's attitude on the constitutional question," he said. "It didn't change it at all. What actually happened was [the number of] unionists who gave transfers to nationalism and to Sinn Féin actually declined. The election actually brought more voters for both national identities."
He added that there was a more cross-community support for the union than for a united Ireland. "The majority of people in Northern Ireland support staying in the union. There's a significant share of the Catholic population that wants to stay within the union. We have to understand and appreciate more the reasons for that. "
Shirlow's analysis was challenged by commentator Patricia MacBride, who said: 'There has been a change in attitudes in the unionist community in my experience, regarding attitudes to a united Ireland. It's not a sea change. It's about being much more open to how would it look, what would it be like?'
'Those conversations are happening and another thing that is happening is that people are becoming more fluid in how they identify' she said, pointing to recent surveys showing a rise in the number of people who identify as Northern Irish rather than British.
Sinn Fein Vice-president Michelle O'Neill struck a conciliatory note in the following keynote, saying 'It is our task to listen to unionism. We must persuade those people, sectors and communities why it’s in their political and economic interests to share a United Ireland.'
A second panel looked at the role of the Irish community in Britain. Writer Geoff Bell compared the current scene to previous phases of mobilization, and noted that no organised campaign on the issue of Irish unity currently exists in Britain.
Professor Mary Hickman gave an overview of the demographics of the Irish community. She argued that all political parties in Britain should be looked at as potential vehicles, and said that lessons needed to be learned from the Irish4Europe campaign, which had failed to engage older settled immigrants who were more open to the case for leaving the European Union.
Older immigrants were also those most attached to the case for Irish unity, she noted, while younger immigrants had been mobilized around single issues such as Brexit, equal marriage and abortion, the latter a question on which she challenged Sinn Fein to move further.
Kevin Meagher, author of A United Ireland: Why Unification Is Inevitable and How It Will Come About, gave a tightly focused account of the case for his thesis. "British parties should make a clear and unambigous manifesto commitment to facilitate an Irish border poll in the next parliament, a referendum on Northern Ireland's constitutional status. This is not to take sides necessarily but simply to recognise that all the available evidence suggests that five years from now, British ministers will be legally bound under the terms of the Good Friday Agreement to call one. Let's get ahead of the curve.'
Closing the event former Sinn Fein president Gerry Adams picked up on earlier discussions: 'Geoff Bell said there's no organised campaign here. That's a question for all of you. I don't live here. There's an organised campaign in Ireland. If I lived here there'd be an organised campaign here. I don't say that in any vainglorious way, but I think that's a challenge for you all.'
It remains to be seen what response that call will meet with, but the current turmoil in the British-Irish relationship perhaps makes it clearer what role the Irish in Britain could play. The argument for unity ultimately has to be won in Ireland, but when that time comes there may need to be pressure on the British government whose commitment to other aspects of the Good Friday Agreement is already open to doubt.