In 1910 Thomas Matthews published a collection of several Welsh documents held in the "Archives Nationales" in France. Covering such figures as Llewelyn Fawr, the Bishop of Menevia, and Owain Glyndŵr, these documents provide an important window into medieval Welsh history. With this volume, the editors have reproduced Matthews's edition and have supplemented it with essays that provide introductions to the original work and its author, consider the documents from a contemporary perspective, revise Matthews's original evaluation, and take note of recent developments in the scholarship relating to this field.