Not quite Scotland, but King Offa of Mercia minted gold coins containing Arabic script in the style of Caliph al-Mansur of Baghdad in the mid-8th century.

Westerns think of the era of post Roman downfall as a 'dark age', but it was really an age of global trade links being established by technological improvements. Norse longships that could run on ocean and way upriver. Arab warriors incorporating horses into their mobile attacks. And a BIG example of the establishment of Arabic as a wide-ranging spoken and then written administrative language, after the introduction of paper-making from China.