6th Cavalry Group
It had entered the war with the task of operating as the Third U.S. Army's primary land intelligence unit. Known additionally in this capacity as the Army Information Service, the 6th Cavalry Group roved ahead in armored cars and jeeps and kept Third U.S. Army HQ (called 'Lucky Forward') informed of both German and American troop dispositions and locations. This allowed Gen. Patton to often know more about where his men were than did the corps and divisional commanders. Because of this the 6th Cavalry Group was informally nicknamed 'Patton's Household Cavalry.'
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