The company began in Chicago, Illinois, in 1918 as a small producer of amateur radio equipment. The name "Zenith" came from its founders' call sign, 9ZN, and Zenith Radio Company was formally incorporated in 1923. Zenith introduced the first portable radio not long after this, and would eventually go on to invent such things as the wireless remote control, FM multiplex stereo, high-contrast and flat-face picture tubes, and the MTS stereo system used on analog television broadcasts in the US and Canada. Zenith was also one of the first companies to introduce a digital HDTV system implementation, parts of which were included in the ATSC standard starting with the 1993 Grand Alliance.

The last logo used during the US-owned period, outside Zenith's impressive corporate headquarters in Glenview, IL in 1995.

In the 1980s, Zenith fell on hard times as more and more of their market share went to Japanese sets with lower prices. In 1979, they got into the computer business with the purchase of Heath Company and their H-8 computer kit; Zenith renamed Heath's computer division Zenith Data Systems, and eventually sold ZDS and Heath to Groupe Bull in 1989 to raise money for its HDTV research efforts. Zenith changed its name to Zenith Electronics Corporation in 1984, to reflect its interests in computers and CATV, and since it had left the radio business two years earlier.

By 1990, Zenith was in trouble, and looking more and more attractive to a hostile takeover. To avoid this, Zenith sold 5% of itself to LG Electronics as part of a technology-sharing agreement. With their analog line aging (the last major update to the line had been the System³ chassis in 1978), and the adoption of HDTV in the US years away, Zenith's prospects were dim. Eventually, LG would raise its stake in Zenith to 55%, enough to assume a controlling interest. Zenith eventually filed for Chapter 11 bankruptcy in 1999, and in exchange for its debts, LG offered to buy the part of Zenith it didn't already own. During this era, some of Zenith's products were being OEMed under the Admiral name.

1952 American Advertisement For Clock-Radio

Zenith Radio
1952 Advert for the Zenith Crest