Answer:
The start of WWII. WWI was a very big cause of WWII. WWI led to depressions in Germany, Italy, the Soviet Union, and many more places which in turn caused powerful people to rise in many different countries. These countries in which a person of power rose each had some part in the start of WWII.
Saratoga- the continental army preserved and won the decimated burgoynes troops, cut off supply routes and Burgoyne never received his promise and desperately needed reinforcements ( found online so change to oun words)
Yorktown-after three weeks of nonstop bombardment birthday and night from artillery Cornwallis surrendered to Washingtonian the field at Yorktown ending the war ( also found online)