Adrienne, The 320th Engineer Battalion (Combat) was an organic unit of the 95th Infantry Division. That is to say, that they were assigned to them. I checked the list of detachments (Temporary re-assignment) from the 95th Division, and the 320th ECB (Engineer Combat Battalion) was never detached temporarily. So any movement by them, was for the entire division as a whole.It was common for divisions to change assignments from corps to corps, or to and from different armies as tactical needs changed. It is important to remember that the U.S. had several armies in Europe. The 1st Army (Commanded by Gen. Courtney Hodges), the 3rd Army (Gen. Patton), 7th Army (Gen. Patch), 9th Army (Gen. Simpson), and later the 15th Army (Gen. Gerow and later Patton).The 95th division moved around quite a bit. From 7/7/44 to 10/9/44 they were in the 9th Army. 10/10/44 to 2/4/45 they were in the 3rd Army. 2/5/45 to 2/4/45 they were back in the 9th (With just a brief assignment in the British Ninth Army).The period of time that you mention (Crossing the Siegfried line) is late November, 1944 during which the 95th Division was assigned to the XXth Corps (Commanded by Gen. Walker), who answered to Patton.The XXth saw very heavy action at that time fighting for the Metz fortifications and later the crossing of the Saar River. Patton's shift to north is most likely a reference to his actions during the Battle of the Bulge. As Americans became surrounded at Bastogne, Patton turned some of his forces to the north to attack the southern part of the German salient and punch through to save the surrounded troops. Not all of his 3rd Army troops took part in the move to the north. Some were left behind to hold the front and ending up guarding a very large portion which was normally held by many more divisions,resulting in very thin lines.The 95th was one of those divisions that was expected to guard more than it's normal share of the front beginning on December 19th, 1944 in what has become known as the Pattons' Ghost Corps front. You will have better luck searching for the history of the 320th Engineers if you search variations of 320th ECB, 320th Combat Engineer, or research the history of the entire 95th Division and look for references to the 320th Engineers.(Not the same as the 320th Engineer Company, or 320th Infantry Regiment,you want the 320th Engineer Battalion). _http://www.lilliputmodel.com/articulos/rabanal/95division/95division_ing.htm_ (http://www.lilliputmodel.com/articulos/rabanal/95division/95division_ing.htm) Rick