Constantinople was surrounded on all sides by a defensive wall and was well supplied, making it resistant to sieges. The Ottomans were only able to capture the city due to one of the city gates being left slightly ajar, allowing them to quickly bypass the wall and overrun the defenders.
<span>The four river valley civilizations were the Tigris & Euphrates Valleys, the Nile River Valley, the Indus River Valley, and the Yellow River Valley. Civilizations developedaround rivers because their waters provided places to hunt and fish. Also, as the rivers flooded, the lands around them became fertile.</span>Mar 2, 2015
Feudal England<span>, </span>Germany<span> and BLANK </span>were the leading powers of the age<span>. France is your answer
Hope I could be of help </span>
Bring their culture with them