[QUEEN MARY'S "CASKET LETTERS"]. [BUCHANAN, George (1506-1582)]. De Maria Scotorum Regina, totaque eius contra Regem coniuratione fodo cum Bothuelio adulterio, nefaria in maritum crudelitate & rabie, horrendo insuper & deterrimo eiusdem parricidio: plena & tragica plane Historia. [London: John Day, 1571]. Small 4to. [ii], 1-122, [iii], [1, blank] pp. Approximately 5 1/2 x 3 3/4". Contemporary full calf ruled in blind, spine lettered in gilt.

Spine and board edges darkened, binding quite worn, soiled, scuffed, later endleaves and blanks, first and final text leaves toned, some soiling in text, numerous contemporary ink notes throughout in an unknown hand (notes are in Latin). Very good. THE SCARCE FIRST EDITION OF THE INFAMOUS "CASKET LETTERS". With the catchwords, "Interea" on p. 7, and "quidem" on p. 53, as called-for. The first 30 or so pages are attributed to George Buchanan, and the other pages are attributed to Thomas Wilson. These letters are the "casket letters" which were used in evidence against Mary, Queen of Scots, allegedly demonstrating her collusion in the death of her husband, Lord Darnley.