Before 1960, almost all comparativists studied English literature, German literature, and French literature, with occasional forays into Italian literature (primarily for Dante) and Spanish literature (primarily for Cervantes). One monument to this approach is Erich Auerbach's book Mimesis, a survey of techniques of realism in texts whose origins span several continents and three thousand years.
The field today, in contrast to this relatively predictable older model, has become extraordinarily diverse: for example, comparativists routinely study Chinese literature, Arabic literature, and the literatures of most other major world languages alongside English and Continental European literatures.
Literary theory is popular in many departments of comparative literature, perhaps even more so than in English studies. However, many exceptions exist, and a more textual, less philosophical approach to literary criticism is practiced alongside theory in all comparative literature departments.