The Casket letters were eight letters and some sonnets said to have been written by Mary, Queen of Scots, to the Earl of Bothwell, between January and April 1567. They were produced as evidence against Queen Mary by the Scottish lords who opposed her rule. In particular, the text of the letters was taken to imply that Queen Mary colluded with Bothwell in the murder of her husband, Lord Darnley. Mary's contemporary supporters, including Adam Blackwood, dismissed them as complete forgeries or letters written by the Queen's servant Mary Beaton. The authenticity of the letters, now known only by copies, continues to be debated. Some historians argue that they were forgeries concocted in order to discredit Queen Mary and ensure that Queen Elizabeth I supported the kingship of the infant James VI of Scotland, rather than his mother.