Rosa Luxemburg holds an enduring fascination as a radical socialist committed to democratic values, and a woman whose charismatic personality and impassioned speeches inspired her followerswithout resort to bureaucratic organisation. Her assistant and friend Mathilde Jacob was Rosa Luxemburg's mainstay during her years of imprisonment in the First World War. 'My dearest Mathilde' provided material and emotional support, organised Rosa Luxemburg's clandestine communication with the outside world, and herself played a key role in the illegal work of the Spartacus group. When revolution broke out in Germany in 1918, she sought unsuccessfully to protect Rosa Luxemburg in the tragic events that led to her death.

Mathilde Jacob's memoir, written as testimony of 'love for a person and for a cause', and sent abroad for safe-keeping when she fell victim to the Nazis, was unknown to Rosa Luxemburg's early biographers and has only recently been published in Germany. It paints a vivid portrait both of Rosa Luxemburg herself, and of the group of friends - Karl Liebknecht, Leo Jogiches, Clara Zetkin and Paul Levi - that with her made up the Spartacus leadership.