[3][4][2] Aerojet traces its origins to the General Tire and Rubber Company (later renamed GenCorp, Inc. as it diversified) established in 1915, while Rocketdyne was created as a division of North American Aviation in 1955.

Due to the studio and rocket businesses, General Tire & Rubber came to own a great deal of property in California.

Its internal facilities management unit began commercializing its operations, landing General Tire & Rubber in the real estate business.

Aerojet converted these former gold fields into one of the premier rocket manufacturing and testing facilities in the Western world.

Located 15 miles (24 km) northeast of Sacramento along U.S. Highway 50, the properties were valuable, being in a key growth corridor in the region.

RKO General ran into difficulties with the Federal Communications Commission (FCC) during license renewal proceedings in the late 1980s.

Steel Partners II had previously attempted a hostile takeover in 2004, and forced the deal after complaining about "significant underperformance and deterioration of share price".

[14] In January 2010, Scott Seymour, the former head of Northrop Grumman Integrated Systems from 2002 to 2008, was appointed permanent CEO of GenCorp, Inc. and Neish resigned.

[15] In July 2012, GenCorp, Inc. agreed to buy rocket engine producer Pratt & Whitney Rocketdyne from United Technologies Corporation for $550 million.

[31] L3Harris named former CTO Ross Niebergall as president of the new Aerojet Rocketdyne business segment,[2] which would now be headquartered in Palm Bay, Florida.

[32] On 13 October 2017, it was reported that Aerojet Rocketdyne completed a keystone demonstration on a new X3 ion thruster, which is a central part of the XR-100 system for the NextSTEP program.

During the demonstration, it broke records for the maximum power output, thrust and operating current achieved by a Hall thruster to date.