4. Transferred to Péronne by way of Sedan, Charleville, Hirson, and Bohain, the 121st Division went into line on the left bank of the Somme on May 18.
5. On July 1, while in this sector, it was surprised by the French offensive and suffered heavy losses (numerous prisoners).
6. Relieved on July 4, it was put at rest and reorganized.
Russia.
7. On July 18 it entrained for the Eastern Front. (Itinerary: Aix la Chapelle-Cologne-Thorn, Warsaw, and Brest-Litowsk.)
Kovel.
8. Taking over the Kovel sector on July 26, it launched counterattacks, in which it was sorely tried.
1917.
Narotch Lake.
1. At the beginning of January, 1917, the 121st Division left the Kovel sector to go into the region of Narotch Lake and stayed in the latter place until May 17.