I came across this old photo on the Irish Examiner website and had to look twice when I read the caption. ‘The Irish Army on manoeuvres near Ballincollig, Co Cork, in July 1940.’ Ballincollig? Surely not, it must be the outskirts of Berlin. However, following further research, the distinctive German style helmet was in fact made by the Vickers Company of Northern Ireland with the internal linings and fittings produced by T. Smith & Sons, Dublin in 1927 following an order made by the Irish Defence Forces.
The Defence Forces originated as the Irish Volunteers and were founded on 25 November 1913 at a public meeting held in the Rotunda Rink in Dublin. Over the next ten years, conflict ensued which included; the Easter Rising, War of Independence and the Civil War. After, relative peace was restored in Ireland when a ceasefire was called on 24 May 1923. Following ‘the end of the Civil War the new state set about providing a legal status for its armed forces. Under the Defence Forces (Temporary Provisions) Act, 1923 the Executive Council formally established Óglaigh na hÉireann on 1 October 1924. A Military Mission was sent to the USA in 1926 to study organisation and training methods. As a result, training was placed on a proper footing with the establishment of a Military College, Corps and Service Schools.’ 
Around this period, the newly formed Defence Forces began looking for a new steel helmet. Initially, the French Adrian helmet was tested but proved unsatisfactory, although the helmet compared favourably when tested against modern helmets in 2020. The next helmet considered by the Irish was the German Stahlhelm. However, under Article 170 of the Treaty of Versailles, Germany was prohibited from manufacturing and exporting ‘arms, munitions and war material of every kind’ to foreign countries. To overcome this problem, the Irish Free State commissioned new helmets based on the German design.
Although similar in appearance, the Irish helmet, painted dark green, had a number of differences. The chinstrap had only ‘one adjustment slide’ whereas the German equivalent had two. Obviously, a key difference was the Vickers helmet had the Irish Defence Force badge on the front of the helmet. Although, interestingly, if you look at the photo, not all helmets have this badge. Peter Suciu speculates that the badges were not installed by Vickers but instead were fitted by an Irish company and ‘it is reasonable to suggest that only helmets intended for an officer would have gone through this extra step.’
The Vickers helmet was used up until 1940 when they were replaced with the British Mark II. However, they old helmets were not completely retired. During the Emergency; World War 2, they were painted white and redistributed to various emergency services. A number of helmets are still in circulation and in 2013, ‘an early Irish Army Vickers Helmet’ went under the hammer at Adams fetching a price of €120. For more about the restoration of the Irish Vickers Helmet check out http://www.frontiernet.net/~masullivan/vickers/Irish_Helmet.htm
 https://www.irishexaminer.com/viewpoints/analysis/irish-examiner-archives-1940s-were-a-decade-of-war-and-want-mdash-and-yet-change-317108.html  https://www.military.ie/en/public-information/defence-forces-museums/defence-forces-history/history-of-the-army/  https://www.stripes.com/news/wwi-french-steel-pot-outperforms-modern-us-army-helmet-in-averting-overhead-blast-injuries-study-finds-1.619409  https://net.lib.byu.edu/~rdh7/wwi/versa/versa4.html  https://alexanderandsonsrestorations.com/project/m1927-irish-vickers-helmet/  https://www.militarytrader.com/militaria-collectibles/tommys-jerry-pot  https://www.adams.ie/48071/An-early-Irish-Army-Vickers-Helmet-the-pads-and-leatherwork-stamped-T-Smith-Son-Dublin-1927-L-approx-18cm-high-The-Vickers-or-M1927-Helmet-was-introduced-in-Ireland-in-1926-and-remained-in-use-u?ipp=50&keyword=&view=lot_detail