Era
20th century
31
1951-
11
1865-1950
9
1900-1999
9
1865-1951
4
19th century
3
1929
2
1933-1945
2
Since 1900
2
1700-1899
1
1775-1865
1
1835-1933
1
1861-1865
1
1865-
1
1865-1999
1
18th century
1
1900 - 1999
1
1917-
1
1917-1998
1
1918-1961
1
1929-1968
1
1948-
1
1980-
1
1989-
1
2010
1
Civil War, 1861-1865
1
Since 1800
1