However, the Irish government introduced several measures in an attempt to improve recruitment and retention,[citation needed] and in 2024 inductions to the Defence Forces exceeded discharges.

The National Army's first Commander-in-Chief, Michael Collins, envisaged the new Army being built around the pre-existing IRA, but over half of this organisation rejected the compromises required [citation needed] by the Anglo-Irish Treaty which established the Irish Free State, and favoured upholding the revolutionary Irish Republic which had been established in 1919.

Both forces continued to use the Irish-language title Óglaigh na hÉireann, which had previously been used by both the original IRA and its predecessor, the Irish Volunteers of the mid-1910s.

The British were applying increasing pressure on the government to assert its control over the anti-Treaty units of the IRA who had occupied the Four Courts in Dublin; this garrison had kidnapped JJ O'Connell, a lieutenant-general in the National Army.

In the early weeks of the Civil War, the newly formed National Army was mainly composed of pro-Treaty IRA units, especially the Dublin Guard, whose members had personal ties to Michael Collins.

The anti-Treaty IRA were also dislodged from Limerick and Waterford in that month and Cork and County Kerry were secured in a decisive seaborne offensive in August.

With the end of the Civil War, the National Army had grown too big for a peacetime role and was too expensive for the new Irish state to maintain.

In addition, many of the civil war recruits were badly trained and undisciplined, making them unsuitable material for a full-time professional army.

The Special Infantry Corps was established to perform the army's first post-war duty, breaking the strikes of agricultural labourers in Munster and south Leinster, as well as reversing factory seizures by socialists.

[11] Richard Mulcahy, the new Irish defence minister, proposed to reduce the army from 55,000 to 18,000 men in the immediate post-Civil War period.

An all-Irish language-speaking unit was created – An Chéad Chathlán Coisithe (English: The First Infantry Battalion) was established in Galway, and functioned exclusively through the medium of the Irish state's first official language.

[23][24] This expansion was undertaken in the face of potential invasions from either the Allied or Axis powers (both of whom had drawn up contingency plans to invade Ireland).

[25] In the Christmas Raid of 1939, the remnants of the IRA stole a large quantity of the Irish Army's reserve ammunition from its dump at the Magazine Fort in Dublin's Phoenix Park.

For example, the Donegal Corridor allowed British military aircraft based in County Fermanagh to fly through Irish airspace to the Atlantic, thereby greatly increasing their operational range.

In 1973, an infantry group and some logistical troops were pulled out of Cyprus at short notice to serve in the Sinai desert between Egypt and Israel as part of the UN force that supervised the ceasefire that ended the Yom Kippur War.

On 16 April 1980, soldiers attempting to set up a checkpoint near At Tiri were attacked by members of the South Lebanon Army (an Israeli-backed Christian militia).

From 25 April 1995 to 9 May 1996, Brigadier General P. Redmond served as Deputy Force Commander of UNIFIL during a period that coincided with the Israeli Operation Grapes of Wrath offensive in 1996.

On 14 December 2022, one Irish peacekeeper was killed and seven others were injured in a "serious incident" involving small arms fire in the Hezbollah controlled village of Al-Aqbieh.

In 1997 an Irish Army Military Police unit and a company of transport corps troops were deployed to Bosnia as part of SFOR (1995–2005) and EUFOR (December 2005 to present).

[40] During the UNMIL deployment, a detachment of Irish Army Rangers successfully rescued a group of civilians being held hostage by renegade Liberian gunmen.

Acting on intelligence, twenty heavily armed Rangers were dropped by helicopter, freeing the hostages and capturing the rebel leader.

In announcing the mission, the Minister for Defence recognised the regional nature of the crisis, involving instability in Darfur, Chad and the Central African Republic.

Ireland contributed the second largest contingent of soldiers to EUFOR Chad/CAR, after France, as part of the mission to establish peace in Chad and to protect refugees from neighbouring Darfur.

[45][46] The Irish soldiers conducted operations concerned with the delivery of humanitarian aid, protection of civilians, and ensuring the safety of UN personnel.

[47] There were a number of deployments to the mission, rotating every four months, with the final contingent completing their tour in May 2010:[48] In 2013 the United Nations asked Ireland to send peacekeepers as part of the United Nations Disengagement Observer Force (UNDOF) in the Golan region of Syria, to try to contain the Syrian civil war from spreading into Israel.

The Irish convoy came under small arms fire and a Mowag APC later struck a land mine, damaging the vehicle, when driving out of the attack.

[55] As of 1 December 2015, 493 Defence Force personnel are serving in 12 different missions throughout the world including Lebanon (UNIFIL), Syria (UNDOF), Middle East (UNTSO), Kosovo (KFOR), German-led Battle Group 2016 and other observer and staff appointments to UN, EU, OSCE and PfP posts.

It is also responsible for the driving standards, training and certification, as well as providing vehicle fuels and lubricants, and certain logistics – such as heavy lift capabilities.

In wartime, additional tasks include the provision of a traffic control organisation to allow rapid movement of military formations to their mission areas.

[67][68] Other weapons in use by the Army include the USP 9mm pistol, M203 grenade launcher,[69][70] FN MAG machine gun,[71] M2 Browning machine gun,[72] Accuracy International Arctic Warfare sniper rifles,[73] AT4 SRAAW,[74] FGM-148 Javelin[69][75] Anti-tank guided missile, L118 105mm Howitzer,[76] and RBS 70 Surface to Air Missile system.