Spread disease such as smallpox which killed much of population.
Colonized most of land, taking from natives and forcing them to settle elsewhere.
Introduced them to European items, such as horses, guns, and some farm animals
agree, especially by lease, deed, or other legal contract.
Hope this helps!
The two reasons:
- Britain intercepted the Zimmerman Telegram
- Germany resumed unrestricted submarine warfare
Context/detail:
Public outrage in the US against the Germans swept the nation following the sinking of the British ocean liner, <em>Lusitania</em> -- but that happened before 1917. When a German U-boat (submarine) sank the Lusitania in May, 1915, over 1,000 persons were killed, including more than 100 Americans. The passenger liner was targeted by the Germans because they suspected weapons were being shipped to Britain in the cargo hold of the ship.
Germany managed to stave off American entry into the war at the time by pledging to stop submarine attacks. But a couple years later they resumed such attacks, and there was also an intercepted telegram (the "Zimmerman Telegram") that showed Germany was trying to secure Mexico as an ally against the United States.
In 1917, the US declared war on Germany in response.
The event was called the Great Purge. Several Soviet officials and high ranking people were arrested during this event. Some were even executed.
In general, history is the recorded story of the interaction between "ideas" "people" and "patterns", since it is the way in which people act and make decisions that influences their collective history.