National Archives Director John McDonough said: “The National Archives is delighted to be able to share this important collection as part of its commitment to Ireland 2016. The weekly release of this material will allow visitors to our website to track the movements of those involved in the Rising in the months leading up April 1916.  People will be able to read how key players were identified, followed, and put under surveillance, and read the thoughts of the Detectives tracking them.”

Arts, Heritage and the Gaeltacht Minister Heather Humphreys said the files “give fascinating insight to events leading up to 1916 Rising”.

Ms Humphreys said: “These files begin at the start of June in 1915, and lead right up to 20 April 1916, just 4 days before the beginning of the 1916 Rising. They describe Republican activity in Dublin at the time and include details of intelligence gathered at a number of key city centre locations, such as the shop of Thomas J Clarke at 75 Parnell Street and the Irish Volunteers Office on Dawson Street.

“The files may be 100 years old, but they still paint a fascinating picture of how the Dublin Metropolitan Police were monitoring the people who they believed were plotting Ireland's independence. More than 230 individuals were monitored, with a number of very familiar names cropping up in the files, including Thomas J Clarke, who is mentioned in almost every report, Con Colbert, Seán T Ó Ceallaigh, Seán Mac Diarmada.

“Major events which took place in 1915 and 1916 were also under close surveillance. The files include references to the funeral of Jeremiah O'Donovan Rossa and the Annual Convention of Irish Volunteers. The reports also include details of anti-recruitment and conscription rallies and meetings of the Irish Women's Franchise League.

“There is so much fascinating material about the period before the Rising and I am delighted to see the National Archives making these files available online, which will ensure they are accessible to the greatest possible audience. This is one of a number of digitisation projects taking place as part of Ireland 2016.”

The reports were compiled by Superintendent Owen Brien and submitted to the Under Secretary for Ireland, Sir Matthew Nathan, at Dublin Castle.

The reports describe Republican activity in Dublin during the 11 months preceding the Easter Rising.

The reports detail intelligence gathered at a number of key city centre locations, most notably the shop of Thomas J Clarke at 75 Parnell Street and the Irish Volunteers Office at 2 Dawson Street. Major events which took place in 1915 and 1916 are recorded in the reports, including the funeral of Jeremiah O'Donovan Rossa and the Annual Convention of Irish Volunteers.

The reports also include details of anti-recruitment and conscription rallies, meetings of the Irish Women's Franchise League, and protests against the imprisonment of revolutionaries under the Defence of the Realm Act and the movement of suspects to major events outside of Dublin.

There are over 230 individuals referred to in the reports, principally members of the Irish Volunteers, the Irish Republican Brotherhood and Sinn Féin.

The primary person of interest is Thomas J Clarke, who is mentioned in almost every report, while the other most frequently mentioned individuals include Pierce Beasley, Thomas Byrne, Con Colbert, Bulmer Hobson, Seán Seán T Ó Ceallaigh, Seán Mac Diarmada, John McGarry, Joseph McGuinness, Herbert Mellows, Michael O'Hanrahan, William O'Leary Curtis, Michael Joseph O'Rahilly and James Joseph Walsh.

In total there were approximately 260 files comprising 700 documents which were conserved, listed and scanned. 

The reports will be released on the website of the National Archives on a weekly basis, beginning Monday 1 June 2015, the 100^th anniversary of the first report.

Frequent updates will also be available on the National Archives Twitter account @narireland, which goes live on Tuesday 2 June.

The files can be viewed on the National Archives website at  www.nationalarchives.ie