Third Infantry Brigade:
Ninth Infantry.
Twenty-third Infantry.
Fifth Machine Gun Battalion.
Fourth Infantry Brigade:
Fifth Marines.
Sixth Marines.
Sixth Machine Gun Battalion of Marines.
Second Field Artillery Brigade:
Twelfth Field Artillery.
Fifteenth Field Artillery.
Seventeenth Field Artillery.
Second Trench Mortar Battery.
Other troops:
Second Engineers.
Fourth Machine Gun Battalion.
First Field Signal Battalion.
Second Headquarters Train and Military Police.
Second Ammunition Train.
Second Engineer Train.
Second Supply Train.
Second Sanitary Train.

On October 26, 1917, Brig. Gen. Charles A. Doyen, United States Marine Corps, assumed command of the Second Division as its first commanding general and announced his staff in General Orders, No. 1, with station at Bourmont, Haute-Marne, France. Lieut. Col. Logan Feland, United States Marine Corps, was the first chief of staff. On November 8, 1917, Maj. Gen. Omar Bundy, United States Army, assumed command, published such fact in General Orders, No. 4, November 8, 1917, and was in command of it during the operations in the Verdun and Chateau-Thierry sectors. Maj. Gen. James G. Harbord, United States Army, commanded the division in the Aisne-Marne (Soissons) offensive in July, 1918. Maj. Gen. John A. Lejeune assumed command of the division on July 28, 1918, and retained command until its demobilization in August, 1919. Many Marine officers occupied positions of importance and responsibility on the staff of the commanding general, Second Division. A Marine officer commanded the Seventeenth Field Artillery during the Meuse-Argonne offensive, and other Marine officers commanded battalions of the Ninth Infantry and Fifteenth Field Artillery for a time.

Neither the Marine Brigade nor any other element of the Second Division was the first American unit to enter the front lines since the First Division enjoyed that honor in October, 1917, when it entered the line in the quiet Toul sector.

The Fourth Brigade remained in the Bourmont training area, with headquarters at Damblain, until March 14, 1918, when it commenced movement into subsectors of the Verdun front, the first units of the brigade entering the front line during the night of March 16-17, 1918, with headquarters at Toulon. On April 1, 1918, brigade headquarters was changed to Moscou. The brigade remained on the Verdun front until May 14, 1918, when it proceeded to an area around Vitry-le-François for open warfare training, with headquarters at Venault-les-Dames. In the meantime, on May 6, 1918, Brig. Gen. James G. Harbord assumed command of the brigade, relieving Brig. Gen. Doyen who had been ordered to the United States on account of his physical condition. Brig. Gen. Doyen relinquished command of the brigade most unwillingly, and the reasons for his relief are best set forth in the words of the citation of a Navy distinguished service medal posthumously awarded to him, reading as follows:

By reason of his abilities and personal efforts, he brought this brigade to the very high state of efficiency which enabled it to successfully resist the German army in the Chateau-Thierry sector and Belleau Woods. The strong efforts on his part for nearly a year undermined his health and necessitated his being invalided to the United States before having the opportunity to command the brigade in action, but his work was shown by the excellent service rendered by the brigade, not only at Belleau Woods, but during the entire campaign when they fought many battles.

Gen. Pershing in a letter to Brig. Gen. Doyen stated in part:

Your service has been satisfactory and your command is considered as one of the best in France. I have nothing but praise for the service which you have rendered in this command.

On May 14, 1918, the brigade left the area around Vitry-le-François as it was unsuitable and proceeded to an area around Gisors-Chaumont-en-Vixen, with headquarters at Bou-des-Bois. The brigade was in this area when sudden orders came to move to the Chateau-Thierry sector.

On May 27, 1918, Brig. Gen. John A. Lejeune and Maj. Earl H. Ellis sailed from New York on board the Henderson and arrived at Brest, France, on June 8, 1918.