Catherine Pine was born in Maidstone on 7th May 1864. She trained as a nurse at St Bartholomew's Hospital from 1895 until 1897. After qualifying she remained at St Bartholomew's and in 1900 she was promoted to hospital sister. In 1901 she moved to Great Ormond Street Hospital.
Pine joined the Women Social & Political Union and she was involved with Flora Murray and Louisa Garrett Anderson in running the Notting Hill nursing home that WSPU members went to while recovering from hunger strikes. She also treated Harry Pankhurst, the son of Emmeline Pankhurst. Harry died in the nursing home in January 1910.
On 13th October 1913 she attended a meeting being addressed by Sylvia Pankhurst at Bow Baths Hall. Pine was injured in a struggle with the police during the meeting. Pine was devoted to Emmeline Pankhurst and was her personal nurse after she was released from Holloway Prison in 1913.
According to Elizabeth Crawford, the author of The Suffragette Movement (1999): "Nurse Pine's own nursing home was so besieged by detectives and onlookers that, in order to maintain the calm necessary to the recovery of her patients and in order that she should not lose clients and thereby jeopardize her business, Nurse Pine looked after Mrs Pankhurst, in London." Pine therefore looked after Pankhurst in the homes of Hertha Ayrton, Ethel Smyth and Hilda Brackenbury.
During the First World War she set up a hostel in which to care for illegitimate "war babies". It was housed first in Mecklenburgh Square and then at 50 Clarendon Road. After the war Pine accompanied Pankhurst to USA and Canada. Pine returned to England in 1923.
Catherine Pine died on 14th August 1941.