1915.
The division was formed in April, 1915, by taking three regiments (178th, 182d, and 106th Reserve) from established divisions of the 12th Corps the 12th Reserve Corps (Saxons). In October, 1916, the 182d Regiment was transferred to the 216th Division and was replaced by the 425th Infantry, which was also transferred from this division in March, 1917, and replaced by the 351st Regiment (Saxon).
Champagne.
1. In May, 1915, the 123d Division occupied the region northwest of Rheims.
2. At the end of May it was transported to Lille, where it seems to have been transferred as a reserve; in the middle of June it was in the vicinity of Arras.
Artois.
3. It next occupied different sectors in Artois.
4. In September it held the Souchez front. On October 8 it took part in the attack on Loos and left Artois in the middle of that month.
Flanders.
5. After a rest at Lille the division went to Flanders (November), where it held a sector south of the canal from Ypres to Comines.