No military action led to the start of WW1; the catalyst to WW1 was the assassination of Franz Ferdinand, the archduke of Austria-Hungary. His murder by Gavrilo Princip – a Serbian nationalist, caused Austria-Hungary to declare war on Serbia, which drew the other European countries into the war due to their existing treaties of mutual defense.
Answer:
the black codes
Explanation:
The end of the Civil War marked the end of slavery for 4 million black Southerners. the war left them landless and with little money to support themselves. White Southerners, seeking to control the freedmen (former slaves), devised special state law codes. Many Northerners saw these codes as blatant attempts to restore slavery.
Nobles and knights were obliged to protect those who lived on the manor and provide personal and military service to the king.
I would say the 14th amendment because it gave equal rights and protections under the law.