This extremely rare analysis of the 1939 German invasion of Poland was printed only in limited quantities by the War Department in 1941. Military tacticians were still frantically trying to decipher the new warfighting doctrine fueling the Wehrmacht juggernaut, which the press aptly dubbed "blitzkrieg," or "lightening war." The Campaign in Poland 1939 is a must read for every serious scholar of World War II. It was originally classified since much of its text was based on military intelligence at the time. It remains “must” reading for soldiers and scholars alike, detailing for the reader the comparative fighting strengths of the German and Polish military forces, German plans, Polish plans, and a chronological order of the operations from break-through on September 1-5 to exploitation on September 6-8 to encirclement on 9-14 September and annihilation on 15-28 September. Six original maps are included depicting: terrain, communications and permanent fortifications (map 1); dispositions of opposing forces on August 31 and German Plan (map 2); situation at dark on September 5 (map 3); situation at dark on September 8 (map 4); situation at dark on September 14 (map 5); and situation at dark on September 20 (map 6). There are also concluding comments and insights with excerpts taken verbatim from material prepared by the Military Intelligence Service of the War Department in those chaotic first days of the war. This is a rare book and a valuable reference for every student and scholar of military history.