Eugene Power founded the company as University Microfilms in 1938, preserving works from the British Museum on microfilm. He also noticed a niche market in dissertations publishing. Students are often forced to publish their own works in order to finish their doctoral degree. Dissertations could be published more cheaply as microfilm than as books. As this market grew, the company expanded into filming newspapers and periodicals. ProQuest still publishes so many dissertations that its digital dissertations collection has been declared the official U.S. offsite repository of the Library of Congress.
In his autobiography Edition of One, Power details the development of the company, including how University Microfilms assisted the OSS during World War II. From Power's description, this work mainly involved filming maps and European newspapers so they could be shipped back and forth overseas more cheaply and discretely. Nothing very James Bond-ish.
Xerox owned the company for a time in the 1970s and 1980s, and it was later bought by Bell & Howell (makers of movie cameras used by such luminaries as Leni Riefenstahl and Abraham Zapruder).
The name of the company has changed several times, from University Microfilms to Xerox University Microfilms, to University Microfilms International, then shortened to UMI (possibly meant to distance itself from the seemingly archaic medium of microfilm).
In 1999, the name changed to Bell & Howell Information and Learning, and finally in 2001, settled on ProQuest Information and Learning.
In the 1980s, UMI began producing CD-ROMs and databases of periodicals abstracts and indexes, eventually leading to online subscriptions to databases.
In the 1990s, with many new electronic media available, microform seemed to be on the decline.
The company has tried to ride this wave out and catch the next wave by emphasizing its electronic business, including selling access to online versions of current periodicals, mainly sold to schools, universities or libraries.
Besides offering current periodicals, ProQuest more recently began a project to digitize its entire archive of microfilm. This "Digital Vault Initiative" would include 5.5 billion images, including some of the best existing copies of major newspapers dating back 100 to 150 years, and Early English books dating back to the 1400s.