U+A779 Latin Capital Letter Insular D

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Insular script is a medieval script system originating in Ireland that spread to England and continental Europe under the influence of Irish Christianity. Irish missionaries took the script to continental Europe, where they founded monasteries, such as Bobbio. The scripts were also used in monasteries, like Fulda, which were influenced by English missionaries. They are associated with Insular art, of which most surviving examples are illuminated manuscripts. It greatly influenced modern Gaelic type and handwriting.

The term "Insular script" is used to refer to a diverse family of scripts used for different functions. At the top of the hierarchy was the Insular half-uncial (or "Insular majuscule"), used for important documents and sacred text. The full uncial, in a version called "English uncial", was used in some English centres. Then "in descending order of formality and increased speed of writing" came "set minuscule", "cursive minuscule" and "current minuscule". These were used for non-scriptural texts, letters, accounting records, notes, and all the other types of written documents.