Conversation so far:
How many times did Harriet Tubman get married?
she married a free black man named John Tubman.
When did she get married to John Tubman?
Around 1844.
How many children did they have?
little is known about him or their time together.
How did they meet?
CANNOTANSWER.
When did Harriet first run away?
CANNOTANSWER.
Can you tell me anything else about Harriet's family?
Tubman changed her name from Araminta to Harriet soon after her marriage.

Question: Why did she change her name?
Self-contained rewrite: Why did Harriet Tubman change her name?