Subject
History
240
History and criticism
61
Politics and government
33
Philosophy
30
Criticism and interpretation
28
Civilization
24
Social conditions
12
Social aspects
11
Law
9
Political and social views
9
Religion
9
Economic conditions
8
International relations
8
Military art and science
8
Political aspects
8
Political science
8
Art, Modern
7
Communism
7
Emigration and immigration
7
Islam
7
Presidents
7
Antiquities
6
Christianity
6
Foreign relations
6
Life
6
Motion pictures
6
Physics
6
Science
6
Spanish American literature
6
Cosmology
5
Criticism, interpretation, etc
5
Democracy
5
Discovery and exploration
5
Economics
5
Epidemiology
5
Influence
5
Music
5
Political culture
5
Psychoanalysis
5
Psychological aspects
5
Social life and customs
5
Spanish
5
Anarchism
4
Astronomers
4
Buddhism
4
Christian saints
4
Civilization, Ancient
4
Comparative law
4
Doctrines
4
Earth sciences
4
more ...