Certainly in Britain it changed with the monarch: The period from 1900 to 1914 is called the Edwardian age....
The Early Modern Period
Neutrility
Both UK and USA were the major world powers between 1870 and 1914.
It was considered a Golden Age because the upper class was free to indulge in excess. Meanwhile the workers suffered and were kept silent.
In the United States, it was called the Progressive Era.
Certainly in Britain it changed with the monarch: The period from 1900 to 1914 is called the Edwardian age....
World War I or "The Great War" occurred between 1914-1918
World War II
The Early Modern Period
What Could She Do - 1914 was released on: USA: 20 November 1914
France and Germany both doubled during that time period
To Be Called For - 1914 was released on: USA: 2 September 1914
Called to the Front - 1914 was released on: UK: August 1914 USA: October 1914
Neutrility
Could You Blame Her - 1914 was released on: USA: 22 May 1914
The Hedge Between - 1914 was released on: USA: 16 August 1914