Era
20th century
150
19th century
94
1910-1921
70
1850-1904
32
1864-1916
32
21st century
31
18th century
24
1922-
24
1856-1918
17
1837-1901
14
1922-1949
12
1882-1941
11
17th century
10
1819-1901
9
1872-1949
9
1882-1975
8
Civil War, 1922-1923
8
War of Independence, 1919-1921
8
1901-1910
7
Easter Rising, 1916
7
1564-1616
6
1875-1915
6
1906-
6
16th century
5
1830-1840
5
1846-1891
5
1856-1950
5
1932-1981
5
Revolution, 1775-1783
5
1760-1820
4
1768-1797
4
1792-1822
4
1809-1898
4
1854-1900
4
1862-1927
4
1864–1952
4
1888-1960
4
Revolution, 1789-1799
4
To 1500
4
1667-1745
3
1769-1821
3
1784-1859
3
1829-1882
3
1836-1882
3
1854-1932
3
1890-1922
3
1899-1961
3
1940-1950
3
Colonial period, ca. 1600-1775
3
Famine, 1845-1852
3
more ...