When was Germany involved in WW1?

Germany was involved in World War I from July 28, 1914, when Austria-Hungary declared war on Serbia, and Germany subsequently supported its ally. The war lasted until November 11, 1918, when an armistice was signed, leading to the end of hostilities. Germany played a central role in the conflict, fighting alongside the Central Powers against the Allies. The war ultimately led to significant political and territorial changes in Europe.