Univega was not a manufacturer. It was a trademark of Ben Olken's Lawee distributors in Massachusetts, an importer. They were decent bikes from various sources (Miyata, Akisu and others) mostly in Japan, later/lower end models were from Taiwan. In the late 1990s, the Univega name was sold to Derby, and Univega became a parallel line to Raleigh, with identical models under the two different names. The Univega name was discontinued around 2000 but is now currently being used for roadbikes sold in Europe as the name has a very good reputation.
Univega was first known as Italvegas from 1971 - 1977 or thereabouts.