While Mary had written what would turn out to be her last long work of fiction, she was still being read and 1914 brought a Nelson's Library edition of Red Pottage, some fifteen years after the original debacle with Edward Arnold. But more important, unforeseen events would dominate this year. On 13 June Mary was writing to Rhoda Broughton, one of her staunchest friends of the previous century, with jokes about Percy Lubbock's forthcoming marriage to an unnamed woman (in fact he did not marry during Mary's lifetime), and flippant expressions of jealousy because Victoria was making off with a cool dozen of her friends and inviting them to tea on her own account. Brooke was

This report to her old friend, full of Mary's characteristic irony and humour, is her last extant letter written before the outbreak of the First World War. She had in any case broken off her journal in 1911 and her experience of the next few years is recoverable – in so far as it can be recovered – almost entirely through her correspondence with two old friends, Rhoda Broughton and Sir Matthew Nathan.

The summer of 1914 brought notably hot weather; afterwards people remembered picnics under the trees, and in the first two or three weeks of June Mary was busy arranging motoring parties and issuing luncheon invitations from her house in Ufford. It was on 28 June that the Austrian Archduke Ferdinand and his wife were assassinated, and the question of whether or not war would be necessary, even desirable, began to be debated in the national press – The Times alone of the major papers was initially in favour of such extreme measures.