There was no single leader during WW1. Each country had their own leader.
Kaiser Wilhelm II
Kaiser Wilhelm the Second. Kaiser (derived from Caesar) was the title of the German and Austrian emperors.
The leader of Germany in WW1 was not a king, his title was Kaiser, specifically, Kaiser Wilhelm II
People got evacuated
King George the 5th.
There was no single leader during WW1. Each country had their own leader.
The most powerful leader in Russia during World War I was Nicholas II. In addition, Nicholas Nikolaevich and Aleksei Brusilov were leaders during WW1.
David Lloyd George was the leader of Brittain during ww1
Kaiser Wilhelm II
Franz Joseph
Woodrow Wilson
Kaiser Wilhelm II
King George V
John J. Pershing
Kaiser Wilhelm the Third was the leader of Germany during WW1
Woodrow Wilson