After Chateau Thiery, the regiment refitted. Replacements from all over the United States arrived, becoming about 65 percent of the regiment's enlisted men and nearly 75 percent of the officers. Meanwhile, General Pershing, commander of the AEF on the Western Front, had finally amassed enough troops to form an autonomous American field army. Its first battle would be to pinch off the St. Mihiel salient. The Rainbow Division with the Fighting 69th would participate from the right side pressing northwest from Beaumont assisted by Lieutenant Colonel George Patton's 1st Tank Brigade. Many days of marches through the rain brought the 69th to the jump-off point by 10 September, but the rain delayed the start to 12 September. The Germans sensed the build-up and were in the process of withdrawing, so resistance was light. The regiment captured thousands of Germans in open field fighting while suffering 47 KIA and reached its objective of St. Benoit on 15 September.