Why was the Rally held in Vandalia?
Vandalia was a plan by British investors in 1770 to occupy 2,500,000 acres of land and create a new colony in the Ohio Valley in North America.
Occupy
For what it is worth, Vandalia, Ohio is where the Dayton International Airport is located. The airport hosts the Annual Dayton Air Show and is a short drive from Wright Patterson Air Force Base (home of the USAF Museum).
The air show is an event that attracts aerospace vendors and manufacturers from all over the world. It competes with the Paris Air Show for the claim of the largest such show in the world. Not sure if they still alternate years, but the show used to invite as the featured event either the USAF Thunderbirds or the USN Blue Angels.
Many deals are struck and announced by vendors during the show. I used to work for GE Aviation (formerly GE Aircraft Engines) just south of Dayton in Cincinnati. GE used to queue up a few months worth of orders and announce them at the show in order to make a big splash.
Dayton Air ShowDayton Air Show (Wikipedia)"