The present day Liberty Hall stands upon the site of an older building, a former hotel that was subsequently occupied by James Connolly, who used the building for publication of various propagandist newspapers, and also as a weapons factory for arming and equipping his Irish Citizens Army. Weapons produced at the original Liberty Hall were also used during the Easter Rising of 1916.
The importance of this manufacturing facility increased after an important shipment of weapons from Germany was intercepted. This is actually the main reason why most of the military action during the Easter Rising was confined to Dublin, and why the sensible course of action would have been to postpone the operation.
No one will ever know the full story of what happened during the hours leading up to the launch of the Rising, since all but one of the rebel leaders were executed, and it seems nobody cared to ask the sole surviving military leader for some insight.
One thing that seems clear is that James Connolly and Patrick Pearse had every intention that they should either successfully drive the British out of Dublin (a billion to one shot) or become martyrs in the attempt. This is evident from the wording of the Proclamation issued by Pearse and most likely printed by Connolly, in which they openly mentioned their alliance with Germany.
This they would have been certain would be enough to prod the British into executing them for treason if they were caught. This would elevate them from merely being the leaders of a failed military operation to heroic leaders of a noble insurgency, cruelly martyred by the vengeful British army.
Though Liberty Hall was such an important building to Connolly’s ICA mission, the actual headquarters for the Easter Rising was located in the GPO on Sackville Street (now O’Connell Street). The building was still important; as it was the mustering point for the rebel troops to gather at, before commencing the short march to the GPO.
The leaders of the rebellion had planned everything with great skill and care. This was why it was important that their forces were not seen to be scurrying through the streets like terrorists, but rather as a properly formed up army, marching to the field of battle. In this way, they would be within the bounds of international law and the rules of warfare.
This did introduce some difficulties, however, as it is very difficult to march a force of over 1,000 men through the streets without losing the element of surprise. Fortunately the garrison in Dublin at that time was ridiculously light. Despite the fact that British Intelligence had gotten wind of the plot, knowing even the approximate timing that the Rising was to take place, they did nothing at all to stop it, sent no reinforcements to bolster the defences before the commencement of action, and apparently sent no warning to Dublin Castle concerning what was afoot.
If it had truly been the intention of Pearse and Connolly that they and their fellow leaders be martyred, they were successful in achieving this objective. On their way to be executed, they must have found it difficult to repress their joy. The British response was close to that which had been predicted. Within almost no time at all, every leader except Eamon de Valera was executed, and within five years of that, nearly all of Ireland had been liberated from British Rule.
The main importance of Liberty Hall in the context of the Easter Rising of 1916 was that it provided the rebel forces with a much-needed legitimacy. If the civilians of Dublin saw an army marching, then history would record an army, not merely a gang of opportunists. In a war where the main weapons would be sentiments, putting on a good show was not just a matter of strategy, but it was also a crucial element in achieving eventual victory.