A- He reunited the Franks to fight to fight off Muslim Invasion.
He won a decisive battle against the Muslim invasion during the Battle of Tours after which they never attacked France again and stayed in Spain.
The sit down strike changed the United Automobile Workers from a collection of isolated locals on the frill of the industry, into a major labor union. Leading to the unionization of the domestic United States automobile industry.
... because they opposed the United States becoming a member of the League of Nations.
The League of Nations was the signature idea of President Woodrow Wilson, point #14 of his 14 Points, an international peacekeeping association which he recommended for post-war settlements. The Treaty of Versailles adopted that idea, but back home in the United States, there was not support for involving America in any association that could diminish US sovereignty over its own affairs or involve the US again in wars beyond those pertinent to the United States' own national security.
The culture of Mongolia prizes horses due to their importance to the livelihood of the people who live there, since horses have been essential there for ages.