The 1920's showed a shift from melodic to harmonic improvisation.
The beginning of the 1920's show a general shift from melodic to harmonic improvisation. At the beginning of the decade improvised solos adhered to the melody of the composition, occasionally embellishing it. By the end of the 20's, soloists were developing improvisational techniques that reflected the harmonic framework of the composition.
In 1846, the Oregon boundary dispute between the U.S. and Britain was settled with the signing of the Oregon Treaty. The British gained sole possession of the land north of the 49th parallel and all of Vancouver Island, with the United States receiving the territory south of that line.
Albeit this is a basic answer, World War Two was a major catalyst to an increased focus on internationalism. In addition, financial and political interests (most notably for political interests is the Cold War) are both legitimate reasons to why the United States of America has remained as a major part of international affairs.
Meji.
The Meiji Restoration, referred to at the time as the Honorable Restoration, and also known as the Meiji Renovation, Revolution, Reform, or Renewal, was an event that restored practical imperial rule to the Empire of Japan in 1868 under Emperor Meiji.