Suffragette prisoners did in fact participate in hunger strikes and were eventually force fed. The Women's Social and Political Union awarded prisoners of the campaign with military-style medals, including Hunger Strike medals, which were presented at breakfast receptions after release from prison.
Over the course of this episode it's revealed that Annette Crosbie's character, Clarice Millgrove (the elderly woman whom Nurse Anderson visits and helps with the imminent eviction), was a Suffragette.
This was foreshadowed by the clothing she wears throughout the episode - they are in the Suffragette colours of green and purple.
Sister Monica Joan tells Violet that, like Queen Zenobia, she will conquer. Septimia Zenobia (c. 240 - c. 274) was a third-century queen of the Palmyrene Empire in Syria. In 270, Zenobia launched an invasion that brought most of the Roman East under her sway and culminated with the annexation of Egypt.