Hitler physically invaded Austria, although he also had some support from within the country, from people who believed all Austrians should be Germans. The invasion was later made to look like a voluntary incorporation with the helped of a staged referendum.
<span>the 5th and the 14th amendment to the united states constitution each contain a due process clause
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Explanation:
Russia then declared war on A-H, Germany then on Russia because russia declared war on A-H, then France declared war on germany for declaring war on russia, then Germany tried the schlieffen plan and declared war on Belgium and because belgium was a neutral country the british empire declared war on germany.
In short, the alliances (Triple Entente (Russia, France British Empire)and Centralpowers alliance (Germany,Italy and A-H))caused these countrys to declare war on eachother.