Celtic monks in Ireland around the 7th century were among the most prolific of scribes at this time and they preferred a more workaday script instead of writing entirely in capital letters.
According to historyworld.net, the Cathach of St Columba, dating perhaps from the early 7th century and possibly written by the saint himself, also exemplifies one profoundly influential innovation of the Irish monks.
The scribes write its first letter much larger than the rest of the text and in a grander style to emphasize the beginning of an important passage.
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