I have undertaken to write a military history of Negro troops in the War Of the Rebellion. I have written only Of the military services Of Negro troops; and I have used the generic word Negro because, while many mulattoes were in the service, the Negroes preponderated to an overwhelming degree. In writing Of the remote past, the historian has the hen efit of the sifting and winnowing to which time subjects historical data; but in writing of events within living memory it requires both fortitude and skill to resist the insidious inﬂuence Of interested friends and actors, to sep arate error from truth with an even and steady hand, to master the sources of historical information — to know where the material is, to collect and classify it, although scattered through an almost endless maze of books, news papers, diaries, pamphlets, etc. — and to avoid partisan feeling and maintain a spirit of judicial candor. How far I have succeeded is left to the considerate judgment of the reader.