Era
21st century
49
20th century
44
To 332 B.C
19
20th century --
12
To 332 B.C.
10
1861-1865
9
1929-1968
8
1945-
7
1950-
7
21th century
6
Civil war, 2011-
6
To 146 B.C.
6
1945
5
1970-
5
21st century --
5
17th century
3
1969-
3
1980-
3
19th century
3
19th century --
3
2001-
3
476-1492
3
To 146 B.C
3
1927-2006
2
1941-
2
1946-
2
1997-
2
2002
2
To 1500
2
To 622
2
To 634
2
to 146 B.C
2
-1999
1
1288 - 1918
1
1288-1918
1
1301 - 1373
1
1392-1910
1
1492-
1
1500
1
1517
1
1642-1649
1
1757-1834
1
1783-1865
1
17th century --
1
1801-1873
1
1809-1865
1
1809-1965
1
1826-1885
1
1832-1923
1
1837-1926
1
more ...