December 26, the day following Christmas Day, is called St. Stephen's Day in the Republic of Ireland. It is a public holiday. It commemorates St. Stephen, the first Christian martyr or protomartyr. In Irish (Gaelic) it is called both Lá 'le Stiofán and "Lá an Dreoilín" - the latter translates literally as the "Day of the Wren". This name alludes to several Irish legends linking episodes in the life of Jesus to the wren. In parts of Ireland persons carrying either an effigy of a wren, or an actual caged wren, travel from house to house playing music, singing and dancing. Depending on which region of the country, they are called Wrenboys, Mummers or Strawboys. A Mummer's Festival is held at this time every year in the village of New Inn, Co. Galway. St Stephen's Day is also a popular day for visiting family members.
- A popular rhyme, known to many Irish children and sung at each house visited by the mummers goes as follows:
In the United Kingdom, St. Stephen's Day is known as Boxing Day