Official Records of the American Civil War The Official Records of the War of the Rebellion or often more simply the Official Records or ORs , constitute the most extensive collection of primary source s of the history of the American Civil War . Cornell University lists the official title as , " The War of the Rebellion : a Compilation of the Official Records of the Union and Confederate Armies " . They include selected first - hand accounts , orders , reports , maps , diagrams , and correspondence drawn from War and Navy Department records of both Confederate and Union governments . Union and Confederate Armies . Collection of the records began in 1864 ; no special attention was paid to Confederate records until just after the capture of Richmond , Virginia , in 1865 , when with the help of Confederate Gen . Samuel Cooper , Union Army Chief of Staff Maj . Gen . Henry W . Halleck began the task of collecting and preserving the archives of the Confederacy . In 1866 a joint resolution of Congress authorized the compilation and publication under auspices of the War Department . Eventually , seventeen Secretaries of War were involved in the process . In 1877 , Army Captain Robert N . Scott was appointed by the Secretary of War as director of the Publications Office , War Records . ( Scott ' s name appears in each volume as the preparer , listed with the rank of Brevet Lieutenant Colonel , 3rd U . S . Artillery . ) The original title for the records was " The Official Records of the War of the Rebellion " and they were later renamed " The War of the Rebellion : a Compilation of the Official Records of the Union and Confederate Armies " , which has led to some lasting controversy over the official name for the war . As finally published , the records consist of 138 , 579 pages with 1 , 006 maps and diagrams assembled in 128 books , organized as 70 volumes grouped in four series , published between 1881 and 1901 . Each of the four series of books in the compilation is divided into " volumes " numbered from the beginning of the series with roman numerals . In series II , III , and IV each " volume " coincides with a book . In series I , however , it was found to be usually impracticable , beginning with volume X , to confine " volumes , " as units of content , within single books . Volume X and most subsequent volumes in series I were therefore issued in " parts " distinguished by subsidiary roman numerals , each occupying a separate book . Beginning with volume XXIV , Arabic " serial numbers " were also printed on the backs of the books issued , although these numbers were not included on the title pages , and are therefore not universally used in citations . A final comprehensive index ( Serial No . 130 ) was published in 1901 with remaining additions and corrections . A companion volume , the " Atlas to Accompany the Official Records of the Union and Confederate Armies " , was published in 1895 . It included maps of military operations ( 175 plates ) , a topographic map of the area of operations ( 26 plates ) , and some drawings of weapons , uniforms , insignia , and flags . In 1966 , the U . S . National Archives began publication of a five - volume set that comprised an arguably superior index to the Army ORs , " Military Operations of the Civil War : A Guide Index to the Official Records of the Union and Confederate Armies , 1861 - 1865 " , microfilm publication M1026 . Introductory material to the guide - index offers guidance to readers of the ORs : Because of the enormous volume of material , the lengthy time period of collection and publication , and the constant and continuing process of correction by veterans of both sides still living contemporarily , the records are perhaps the most intensely peer - reviewed documents in historical publication . Historians have argued that some of the modifications made years after the events have decreased the accuracy of the records and were made simply to enhance personal reputations ( or to denigrate the reputations of rivals ) . An additional 100 volumes of previously unpublished reports and correspondence were published by the Broadfoot Publishing Company of Wilmington , North Carolina , from 1995 to 1999 , entitled " Supplement to the Official Records Of the Union and Confederate Armies " . Union and Confederate Navies . Unfortunately , most of the Confederate Navy Department records were lost during the burning of Richmond . Union Navy Department records were preserved , but not until 1884 was work begun by Navy Department librarian , later Assistant Secretary of the Navy , James R . Soley to collect and publish . Intending to partially replace missing reports , many personal narratives were collected and included , often gaining Navy researchers incidental access to draft copies of original reports once thought lost . The official title of publication is " Official Records of the Union and Confederate Navies in the War of the Rebellion " . A proposed third series was deemed unnecessary ; the final volume of series two was published in 1922 . The Navy Department did not publish a comprehensive index to these volumes . Other historical sources . While the Official Records are probably the most - used of all primary sources for historical research on the Civil War , there are other contemporary published works that provide well - sourced insights not constrained by the types of sources compiled by government :