It is useful to find out a little more information before making the decision to return to Ireland. The website of the Citizens Information is a good starting point as it provides a general overview of the sorts of things to consider as part of your decision - click here or go to www.citizensinformation.ie.
Advice from Other Returnees
Hearing how others have found the process of return can also be useful so take a look at the Irish Times Abroad section on returning to Ireland: www.irishtimes.com/life-and-style/generation-emigration/destinations/returning-to-ireland. They also have this useful Generation Emigration Guide to Moving Home from Abroad.
Ireland Move Club (http://irelandmoveclub.com/) also has a number of forums dedicated to the subject especially for people returning from the USA. The Department of Foreign Affairs & Trade have set up 'Global Irish' which also contains useful information to consider on coming home – see www.dfa.ie/global-irish/coming-home/. Recently Irish Around Oz have set up a facebook group for Irish people who are moving back to Ireland from Australia and elsewhere - see http://irisharoundoz.com/blog/2016/07/09/irish-expats-returning-ireland/.
Information on Irish Citizenship is available from the Irish Naturalisation and Immigration Service (INIS) website: http://www.inis.gov.ie/en/INIS/Pages/Citizenship
General information on Irish Citizenship through birth or descent can also be found at the website of the Citizens Information at: www.citizensinformation.ie/en/moving_country/irish_citizenship/irish_citizenship_through_birth_or_descent.html
Irish Prisoners returning to Ireland
The Irish Council for Prisoners Overseas (ICPO) works on behalf of Irish prisoners overseas, providing information, advocacy and support to prisoners and their families. They have two offices, one in London working with Irish born prisoners in the UK, and one in Maynooth working with Irish prisoners in the rest of the world. You can read their leaflet, ‘Irish Prisoners Overseas: A Step-By-Step Guide to Preparing for Release’ and also see thier website www.icpo.ie for more information.