What was the name of the Brontës' aunt who raised them?

The Brontës’ aunt who helped raise them was Elizabeth Branwell.

Known to the children as Aunt Branwell, Elizabeth was the younger sister of their mother, Maria Branwell Brontë. After Maria died in 1821, Elizabeth left Cornwall and moved to the Brontë household in Haworth, Yorkshire. She remained there for the rest of her life, helping Reverend Patrick Brontë care for his six children.

Elizabeth was not their legal parent, but her role was much more than that of a visiting relative. She ran the household, supervised the children’s daily routines, and helped educate them. She encouraged their reading by subscribing to magazines and supported their intellectual lives. Her financial help later contributed to Charlotte and Emily’s time studying in Brussels.

The answer is sometimes confused with Maria Branwell, who was the children’s mother, not their aunt. Charlotte Branwell and Anne Branwell were not the aunt who raised the family. Elizabeth died in Haworth in 1842, aged 66, after an intestinal illness. Her years with the children helped create the stable home in which the Brontë siblings developed their writing and imaginary worlds.