Era
20th century
102
19th century
52
1960-
13
18th century
12
1945-
12
1985-1991
8
1989-
7
21st century
7
1789-1900
6
1991-
6
1837-1901
5
1933-1945
5
Civil War, 1861-1865
5
1815-1861
4
1871-1918
4
1918-1945
4
1919-1947
4
1783-1865
3
1848-1918
3
1869-1948
3
1901-1910
3
1910-1943
3
1914-1945
3
1918-1933
3
1938-1945
3
1945-1960
3
1945-1989
3
1990-
3
16th century
2
1765-1947
2
1775-1865
2
1782-1852
2
1789-1799
2
1789-1815
2
17th century
2
1801-1917
2
1836-1909
2
1838-1909
2
1846-1891
2
1861-1865
2
1867-1914
2
1867-1918
2
1888-1918
2
1910-1921
2
1914-1944
2
1917-1936
2
1918-1938
2
1918-1960
2
1922-
2
1943-1955
2
more ...