Do Not Capitalize > If you are referring an academic department, remember to write it in lowercase.
You can only capitalize when you come up with a proper noun
• The department of English.
• The department of mass communication.
• The department of arts.
• The department of Canadian literature.
• The department of history.
In the above examples, English and Canadian are both proper nouns. That is why, AP Style allows them to be capitalized. However, the words mass communication, arts and history are common nouns; and hence, cannot be capitalized.
Capitalize if it is a formal name
According to AP Style, if you are referring a unit by its official full name, then it is necessary to capitalize it. For example,
• The Department of European Union.
• The School of Thoughts.
• The Department of History.