How the rebel forces were deployed in Dublin

As well as the GPO, City Hall, and St Stephen's Green, the rebels sought to establish strongholds in key areas of the city which would allow them to control or cut off communications with the rest of the country. Their diminished numbers and gaps in their planning, however, meant that their success was patchy. The First Battalion occupied the Four Courts and a range of buildings on North King Street and Church Street, and moved as far north as St Peter's Church in Phibsborough, but did not attempt to occupy the strategically important Broadstone Station. The Four Courts garrison saw action early on Monday afternoon, when it fired on a detachment of Lancers escorting ammunition trucks on their way to the Magazine Fort in Phoenix Park. One small section of the battalion moved across the river and occupied the Mindicity Institute near Queen's Street Bridge.

Eamonn Ceannt's Fourth Battalion mobilised at Emerald Square, just north of Dolphin's Barn and moved off down Cork Street to occupy Jameson's Distillery on Marrowbone Lane and the straggling group of buildings at the South Dublin Union, west of the Guinness Brewery. The SDU was the country's biggest poorhouse, housing 3,000 destitute people. Robert Holland, who ended up in the distillery, found it occupied by "more women than men" - many of them from the Donore Avenue branch of the Gaelic League, whose céilí he had attended the night before.

The Third Battalion, led by Eamon de Valera, had its headquarters in Boland's mill and bakery on Grand Canal Street, to the south-east of the city. Its strategic ambitions were to control the railway lines to the south, to "dominate" Beggar's Bush barracks, and to occupy the vital harbour at Kingstown (Dún Laoghaire). A lack of numbers (exacerbated by de Valera's refusal, uniquely among the rebel commandants, to have women in his ranks) meant, however, that the only significant outposts were at Westland Row station and a small detachment at Mount Street Bridge.

Thomas MacDonagh's Second Battalion, of which Oscar Traynor was part, had intended to occupy Amiens Street station, thus preventing the arrival of troop reinforcements by train from Belfast. In the confusion, however, part of the battalion spent most of Monday and Tuesday moving between Fairview and Parnell Square. The main body moved down to St Stephen's Green, and then on to occupy Jacob's factory on Bishop Street. Along the way, it acquired a new vice-commandant, John McBride, leader of the Irish Brigade in the Boer War, who turned up in a fine blue suit and white spats, bearing nothing more lethal than a malacca cane. A small 10-man unit of the Citizen Army occupied Davy's pub on the northern end of Portobello Bridge to block the movement of troops from Portobello Barracks. It came under heavy attack early on Monday afternoon and was forced to withdraw.