Here is a Welsh alphabet poster titled "Y Wyddor" ("The Alphabet") which dates all the way back to 1900.
The contents of the poster is based on the alphabet of the great antiquary T.C. Evans of Llangynwyd (unrelated but a home of the Mari Lwyd). It was also illustrated by his son, Christopher Evans... and I think he did a fine job!
The poster was a staple of Glamorgan schools throughout the early twentieth century, a time of mini revival for the Welsh language within classrooms following the previous Draconian measures (such as the Welsh Not) to eradicate it in the preceding decades and centuries.
(Image Credits: Amgueddfa Cymru)
