To fulfill President Nixon's "Peace with Honor" and "Vietnamization" directives, the US forces in Vietnam began to be withdrawn. Major units left country and the units that stayed found the replacement stream almost cut off. The chart below shows the official departure dates of the major units. In fact the units were withdrawn from the field and stood down to prepare for departure sometimes as much as one month before they actually departed.
AUGUST 1969 9th INFANTRY Division, 1st and 2nd Brigades
NOVEMBER 1969 3d Marine Division
APRIL 1970 1st INFANTRY Division
APRIL 1970 4th INFANTRY Division, 3rd Brigade
SEPTEMBER 1970 9th INFANTRY Division, 3rd Brigade
OCTOBER 1970 199th INFANTRY BRIGADE
DECEMBER 1970 25th INFANTRY Division, 1st and 3rd Brigades
DECEMBER 1970 4th INFANTRY Division, 1st and 2nd Brigades
APRIL 1971 1st Marine Division
APRIL 1971 25th INFANTRY Division, 2nd Brigade
APRIL 1971 1st Cavalry Division, 1st and 2nd Brigades
APRIL 1971 11th Armored Cavalry Regiment
AUGUST 1971 1st Brigade 5th INFANTRY DIVISION
SEPTEMBER 1971 173rd Airborne Brigade
NOVEMBER 1971 AMERICAL DIVISION, 11th and 198th Brigades
JANUARY 1972 101st Airborne Division
JUNE 1972 1st Cavalry Division, 3rd Brigade
JUNE 1972 AMERICAL Division, 196th Brigade