Isabel was the youngest of three sisters born into a working-class family in
Tyneside. Despite the family's limited means, she was able to obtain a high school education, and won a scholarship to
Sunderland Teacher Training College. In 1920, she was a founding member of the
Communist Party of Great Britain (CPGB), one of only five women delegates to attend its first congress. In 1921 she married Ernest Brown, a local communist. She lost her teaching post the following year when she became pregnant. She stood unsuccessfully in
Motherwell in the
1929 general election, and for her skill at responding to audience questions. In 1939, Brown was appointed National Women's Organiser for the CPGB. She stood in the
1940 Bow and Bromley by-election, taking only 4.2% of the vote even though she faced only one opponent. Brown was seriously injured in a December 1940
air raid. She was hospitalized for six months and never fully recovered. and from the Central Committee in 1947. She stood in her final election at
Kilmarnock in 1948, but again failed to come near winning the seat. Despite increasingly poor health, Brown continued to speak on behalf of the CPGB, and to teach and attend conferences until her death in October 1984. ==References==