The Negro in the American Rebellion: His Heroism and His Fidelity

This book documents the participation of both free blacks and slaves during the Civil War, as well as a background of African American participation in the Revolution and War of 1812. 
 
From the preface: 
 
"Feeling anxious to preserve for future reference an account of the part which the Negro took in suppressing the Slaveholders' Rebellion, I have been induced to write this work. In doing so, it occurred to me that a sketch of the condition of the race previous to the commencement of the war would not be uninteresting to the reader. 
For the information concerning the services which the blacks rendered to the Government in the Revolutionary War, I am indebted to the late George Livermore, Esq., whose "Historical Research" is the ablest work ever published on the early history of the negroes of this country. 
In collecting facts connected with the Rebellion, I have availed myself of the most reliable information that could be obtained from newspaper correspondents, as well as from those who were on the battle-field. To officers and privates of several of the colored regiments I am under many obligations for detailed accounts of engagements. 
No doubt, errors in fact and in judgment will be discovered, which I shall be ready to acknowledge, and correct in subsequent editions. The work might have been swelled to double its present size; but I did not feel bound to introduce an account of every little skirmish in which colored men were engaged. 
I waited patiently, before beginning this work, with the hope that some one more competent would take the subject in hand; but, up to the present, it has not been done, although many books have been written upon the Rebellion. 
WILLIAM WELLS BROWN."