Can someone help me make a conclusion? Research a prominent African American who lived during the 1800s. In a multi-paragraph essay, explain his or her achievements and historical importance.

Here is what I've written, I'm just having trouble with the conclusion :|

Harriet Tubman was an African-American slave and a hero. Harriet was born a slave in a plantation in Dorchester County, Maryland, where she was mistreated and abused with violence that caused permanent injuries. At age twenty, Harriet Tubman escaped at night guided by the North star and traveled many miles all the way to Pennsylvania, where slavery was illegal.

Harriet Tubman then served as the "conductor" for the underground railroad. The Underground Railroad was a network of secret routes and safe houses established in the US which was used by African-American slaves. This network was used to help many African-American slaves escape safely. Harriet helped many slaves escape for eleven years, going back to Maryland risking her own freedom. In 1850, the Fugitive Slave Law was passed in the US which stated that escaped slaves could be captured in the North and returned to slavery, thus Harriet changed the routes to go to Canada.