If you are obese, you may also experience: 1  Trouble sleeping. 2  Sleep apnea. 3  Shortness of breath.  Varicose 1  veins. Skin problems caused by moisture that accumulates in the folds of your skin. 2  Gallstones. Osteoarthritis in weight-bearing joints, especially the  knees.
World War I as a declared state of war lasted from July 28, 1914 to November 11, 1918. After a decade of unstable alliances and military buildups, World War I was triggered in 1914 by the assassination of Archduke Ferdinand. It ended in 1919 with the Treaty of Versailles. (See related question below.)
The war lasted exactly four years, three months and 14 days. Before World War II began in 1939, World War I was called the Great War, the World War or the War to End all Wars. 135 countries took part in World War I, and more than 15 million people died in the war.