When Roman legionaries first set foot on British soil and were met with strange northern men with their faces painted blue, they couldn’t imagine that strange symbols Celts tattooed on their bodies would be so popular some 2000 years later. Not much is known about early Celtic history, but Celtic tattoo designs are very well documented thanks to Irish Illuminated Manuscripts, among other things. Some of the most popular designs come from The Book of Durrow from early 5th century and The Book of Kells, from the middle of the 6th century.