Conversation so far:
What is Selma in relation to the fight for civil rights?
Jimmie Lee Jackson was killed in February 1965 in a voting rights demonstration at the Marion, Alabama, courthouse. His death spurred on the fight for civil rights in Selma, Alabama.
What state is Selma in?
Selma is in the state of Alabama.
What is significant about Selma, Alabama?
The killing of Jimmie Lee Jackson, an African-American, at the February 1956 voting rights demonstration at the Marion, Alabama, Courthouse, spurred in the fight for civil rights in Selma.

Question: why were the people marching?
Self-contained rewrite: Why were the people marching towards Edmund Pettus Bridge on March 7, 1965?