Albrecht, Duke of Wurttemberg was a German General, who achieved military success in different engagements against the opposition. He led the First Battle of Marne and the Battle of Ypres.
Arthur Aitken was a British General, who led the first war with the Germans in East Africa. He was confident of a win in the Battle of Tanga. He, however, failed miserably, and details of his defeat were withheld by British authorities for months.
Sir Edwin Alderson was a Canadian General. He participated in the Second Ypres attack which also saw the first use of gas. His division ceded ground to the advancing German troops to as far as Hill 60.
Duke Emmanuel Philibert Aosta served as a General on the Italian side. He played a significant role in the success of Italy at the Battle of Gorizia. He, however, suffered one of his major setbacks at Caporetto. He was in charge of the Italian Third Army.
Francois Paul Anthoine served as a General in the French forces. He participated in the Third Battle of Ypres, supporting the British.
Moriz von Auffenberg-Komarow served as an Austrian General. He led the Austrian Fourth Army in Galicia. He succeeded in capturing Komarow before his attention was diverted to aid the Austrian Third Army.
The Von Belows served as German Generals. They were both competent commanders who became popularly known for their military achievements.
Robert Lee Bullard “Counter-attack Bullard” served as a U.S General. He led the first major offensive by the United States at Cantigny. He also participated in the Second battle of the Marne.
Sir Douglas Haig served in as a British General. Although portrayed as incompetent, Douglas Haig was a specialist in military training and battlefield strategies. He was successful at Somme, Third Battle of Ypres and Amiens.
There were many other notable Generals who participated in WW1. They played different roles, achieved varied successes and suffered losses in the field.