Bertha Mkhize was born in 1889 in Embo, near Mkhomazi. Her father, an ox wagon driver, died when Bertha was about four years old. After his death her family moved to Inanda. She was one of the first students to attend the Inanda Seminary and thereafter went to Ohlange Institute. Bertha was a teacher until she was about thirty years old, trained as a tailor and then started a tailoring business in Durban with her brother, also a tailor. She stayed in business until 1965 when the Durban City Council forced African businesses to move out of the area.
Mkhize joined the Industrial and Commercial Workers union (ICU) to fight against no notice pay, low wages and curfews and took part in campaigns against passes for women in 1931 and 1936. She was active in the African National Congress Women's League and participated in the 1925 Defiance campaign in Durban. In 1925, as part of this association, Mkhize, along with approximately 500 women marched to the Durban City Council. Here the women waited for the Minister to return from lunch, where Mkhize addressed him to retract the law which would have women seek permission to freely go to Durban. The women were successful in their quest. Bertha attended the founding conference of the Federation of South African Women (FEDSAW) in early 1954 and was chosen one of the organization's four national vice-presidents. In 1956, Mkhize was the President of the African National Congress Women's League (ANCWL). She was arrested in the middle of the night, for treason. This trail would last four years, all those arrested on that particular night for treason were found not guilty. She stayed in business until 1965 when the Durban City Council forced African businesses to move out of the area. Mkhize moved back to Inanda, where she headed a creche at the town library. A young boy called Malkop, introduced her to the Bahai religion-which states all persons are equal, regardless of race. Mkhize translated Bahai books into Zulu and aided in the setting up of centres across Zululand. In 1981, while trying to start an old age home in her community, Mkhize died at the age of ninety-one.