They ambushed the Mongol Empire in China.
        
             
        
        
        
The correct answer is Timbuktu. It became the greatest city because it was a melting pot for traders from all possible nations because it was wealthy and developed compared to other places. It was a cultural and a trading center because the ruler knew how to rule properly and made Timbuktu one of the greatest cities in the world.
        
                    
             
        
        
        
The election of 1860 was one of the most pivotal presidential elections in American history. It pitted Republican nominee Abraham Lincoln against Democratic Party nominee Senator Stephen Douglas, Southern Democratic Party nominee John Breckinridge and Constitutional Union Party nominee John Bell. The main issue of the election was slavery and states’ rights. Lincoln emerged victorious and became the 16th President of the United States during a national crisis that would tear states and families apart and test Lincoln’s leadership and resolve The Civil War
 
        
             
        
        
        
Explanation:
Stock Market Crash of 1929 - Many believe erroneously that the stock market crash that occurred on Black Tuesday, October 29, 1929 is one and the same with the Great Depression. In fact, it was one of the major causes that led to the Great Depression.