Christopher Tombs Antiques Ltd has dated this piece to the 19th Century.
Taken from Wikipedia...
Modern practitioners of bataireacht study the use of the shillelagh for self-defence and as a martial art. Of the practice, researcher J. W. Hurley writes:

Methods of shillelagh fighting have evolved over a period of thousands of years, from the spear, staff, axe and sword fighting of the Irish. There is some evidence which suggests that the use of Irish stick weapons may have evolved in a progression from a reliance on long spears and wattles, to shorter spears and wattles, to the shillelagh, alpeen,[c] blackthorn (walking-stick) and short cudgel. By the 19th century Irish shillelagh-fighting had evolved into a practice which involved the use of three basic types of weapons, sticks which were long, medium or short in length.[22]
Measurements of this example is 21 inches long, and the head is 11 inches x 8 inches.
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Christopher Tombs Antiques Ltd has dated this piece to the 19th Century.
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