Clonmacnoise is a ruined monastery situated in County Offaly in Ireland on the River Shannon south of Athlone, founded in 544 by Saint Ciarán, a young man from Rathcroghan, County Roscommon. Until the 9th century it had close associations with the kings of Connacht.

The Clonmacnoise Crozier is a late-11th-century Insular crozier that would have been used as a ceremonial staff for bishops and mitred abbots. Its origins and medieval provenance are unknown. It was likely discovered in the late 18th or early 19th century in the monastery of Clonmacnoise in County Offaly, Ireland. The crozier has two main parts: a long shaft and a curved crook. Its style reflects elements of Viking art, especially the snake-like animals in figure-of-eight patterns running on the sides of the body of the crook, and the ribbon of dog-like animals in openwork that form the crest at its top. Apart from a shortening to the staff length and the loss of some inserted gems, it is largely intact and is one of the best-preserved surviving pieces of Insular metalwork.