…from his enslaver Mary Brown in Baltimore. Manhattan and Brooklyn abolitionists rallied together to raise the $800 needed for Hamlet’s release. The Freedman’s Bureau After the Civil War, Congress established the Freedman’s Bureau.The Brooklyn Branch, which opened in 1866, assists, educates, and aids free people living in Brooklyn. Peter Croger Peter Croger, one of the founders and trustees of the first African-American church in Brooklyn, establ…