Era
20th century
13
1945-
4
1947-
4
1918-1945
2
1929
2
1932-
2
1945-1970
2
1861-1865
1
1876-1953
1
1886-1961
1
1891-1942
1
1900-1999
1
1902-1968
1
1902-1975
1
1908-1985
1
1916-
1
1916-1981
1
1922-2011
1
1928-1967
1
1932-1995
1
1932-2023
1
1933-1945
1
1940-1945
1
1945 - 1975
1
1945-1975
1
1945-1983
1
1949-
1
1951-
1
2011
1
Boxer Rebellion, 1899-1901
1
Civil War, 1861-1865
1
Civil War, 1936-1939
1
German occupation, 1940-1945
1
Since 1945
1
Since 1951
1