In May 1986, Fuji Heavy Industries Ltd. (now Subaru Corp.) and Isuzu agreed to enter into a joint venture to establish a manufacturing plant in the U.S. Of the many cities originally explored, 13 sites were eventually chosen for further consideration in seven states, including the state of Indiana. In December 1986, Lafayette was selected as the site for the plant and, in March 1987, Subaru-Isuzu Automotive (SIA) was incorporated in Indiana.

In May 1987, ground was broken for the SIA plant and construction began. The original 2.3-million square foot facility integrated operations from stamping to final assembly. Production of the Subaru Legacy and Isuzu pickup began on September 11, 1989. The plant was officially dedicated on October 16, 1989 with a weeklong grand opening ceremony. Throughout the years, SIA Associates have built the Subaru Legacy, Outback, Impreza, Baja and Tribeca, as well as the Isuzu Pick-up, Rodeo, Amigo and Axiom and the Honda Passport. In January 2003, SIA became Subaru of Indiana Automotive, Inc. signifying the sole ownership by Subaru Corp. (then Fuji Heavy Industries Ltd.). SIA discontinued production of Isuzu vehicles on July 23, 2004, and began to build the Toyota Camry on February 28, 2007 under contract with Toyota. Production of the Camry ended in May 2016 to make way for additional Subaru production. Subaru Impreza production began in late 2016 and the Subaru Ascent joined the production mix in May 2018.