The Caubeen Hat is an Irish beret, formerly worn by peasants. It has been adopted as the headdress of Irish regiments of Commonwealth armies.
The name caubeen dates from late 18th century Irish, and literally means “old hat”. It is derived from the Irish word cáibín, meaning “little cape”, which itself is a diminutive form of cába, meaning “cape”.
In the British Army, the caubeen is officially known as the “bonnet, Irish, green”.
In 1916, the Iris h Guards established a pipe band. The pipers’ uniform was a mix of standard service dress and bandsman dress, and also included a khaki bonnet, saffron-coloured kilts and green hose. The khaki bonnet was named “caubeen” by the Guards pipers, and was similar to an oversized beret. Some sources have stated the caubeen’s similarity to the Scottish tam o’ shanter, but the two are different in appearance – the tam o’ shanter retaining much more of a ‘dinner-plate’ effect on the wearer’s head, while the caubeen resembled an oversized beret. The two had different quartermaster codes, meaning that the caubeen was not simply a tam o’ shanter with the toorie cut off, but a purpose-made article in its own right. In World War II, a number of British army regiments adopted both khaki and rifle-green caubeens as their headdress, replacing the GS cap.
Each regiment was distinguished by the feather hackle in their caps: the Royal Inniskilling Fusiliers wore their traditional grey hackles, the Royal Irish Fusiliers wore their traditional green hackles, the Irish Guards and London Irish Rifles were granted blue hackles, and the Liverpool Irish wore a blue-and-red hackle. The Royal Ulster Rifles did not get a band until 1948, so they did not receive their black hackles until 1947.
The caubeen is fashioned on the cáibín worn by Irish military chieftain (1585–1649).