The offensives that started on September 25th 1915 were the Second Battle of Champagne, the Third Battle of Artois and the Battle of Loos.
In the Battle of Champagne, two French armies attacked the Germans on a 24-km (15-mile) front after a four day bombardment. The fighting continued until November, but became increasingly bogged down.
The French suffered 190,000 casualties (men killed, wounded or missing), and took 27,000 prisoners. The Germans suffered 100,000 casualties.
In the Third Battle of Artois, the French captured the town of Souchez, and briefly secured Vimy Ridge – but subsequent gains were limited.
At Loos, the British Army started its biggest offensive of the year, using poison gas for the first time.
After several of weeks of fighting, the British had lost up to 60,000 casualties and made negligible gains. German losses were around 26,000.
Sir John French, Commander-in-Chief of the British Expeditionary Force since the start of the war, was recalled. In December 1915, he was replaced by Sir Douglas Haig.