In January 1884, Douglass applied for a marriage license at District of Columbia City Hall before heading to the home of Reverend Francis James Grimké and Charlotte Forten Grimké , where he married a white woman named Helen Pitts .  The marriage, held January 2,  was not approved by most members of either family. Helen's father, an abolitionist who was previously proud to know Douglass personally, never offered his blessing and refused to visit Washington unless he knew his daughter and her husband were out of town.  Douglass had hired Pitts as a clerk in 1882. She was a graduate of Mount Holyoke College and had been a teacher of freed blacks in Virginia and Indiana.  Interviewed about her marriage, she responded, "Love came to me and I was not afraid to marry the man I loved because of his color."  One newspaper article noted, "Goodbye, black blood in that family. We have no further use for him. His picture hangs in our parlor, we will hang it in the stables." 
In 1845, his autobiography ("Narrative of the Life of Frederick Douglass, an American Slave: Written by Himself") was published to great acclaim. He eloquently depicts the dehumanizing effects of bondage, writing what is often considered one of the finest examples of the slave narrative genre. In describing the efforts of an overseer to break his spirit, Douglass turns the tables to show that it was the slaveholders, not the slaves, who were the brutes to be feared. Douglass toured much of the United states and Europe speaking about his experiences and working for the emancipation of slaves.
He soon became an abolitionist (someone who wants to end slavery), and worked with other abolitionists such as William Lloyd Garrison . He was the most powerful speaker for abolitionism. Frederick also published his own newspaper "North Star". He wrote two books, Narrative of the Life of Frederick Douglass and My Bondage and My Freedom . Douglass spent several years in England and Ireland . During the Civil War , Douglass was the most famous black man in the country, and met Abraham Lincoln . After the War, he served as Ambassador to Haiti and an advocate for equal rights for African-Americans.