Era
1946-
9
2001-2009
7
1809-1865
6
1838-1905
6
19th century
6
Civil War, 1861-1865
6
1945-1989
5
1968-
4
20th century
4
21st century
4
1933-1945
3
1934-
3
1978-
3
1800-1899
2
1861-1865 (Guerre de Sécession)
2
1970-
2
1991-2014
2
2014-
2
2017-2021
2
1882-1945
1
1882-1951
1
1888-1945
1
1889-1951
1
1898-1951
1
1900-1999
1
1908-2008
1
1938-2013
1
1942-2015
1
1945-2001
1
1951-
1
1960-
1
1971-
1
1977-
1
1982-
1
1989-
1
1991-
1
1993-2001
1
2001-
1
2017-
1
2017-2019
1
Since 1898
1
Since 2000
1
Since 2017
1