Both sides were too equal. Neither side could gain over the other, as the fighting went back and forth, often over the same area. This resulted in both sides settling for a relatively static trench warfare.
The entry of the U.S. into the war.
the entry of the U.S. into the war.
the use of chemical weapons.
the use of chemical weapons.
Problems with logistics and communications contributed to the long period of stalemate during World War I. The stalemate happened after the British forces attacked and captured Neuve Chapelle in the Artois region.
The United States entry into the war
Stalemate.
Would you mind reposting your question with a little more information? There was a stalemate in most of World War I, but World War II happened in so many places, that I do not know of the occurence in your question . . .
8 years
no one gains or looses ground
On a Coast Line somewhere
The stalemate generally refers to the Trench warfare in France 1915-1918.