Cardillo notified top-ranking Missouri and Illinois senators and congressmen of his decision on Thursday afternoon.

Cardillo’s process was detailed and deliberate, said Donald Kerr, NGA’s chief of media relations. “It was his decision and his decision alone,” Kerr said.

St. Louis was aided by its two major educational institutions, Washington University and St. Louis University, as well as the agency’s mission to reshape its workforce for the future.

The agency, which is rooted in Lewis and Clark’s landmark Corps of Discovery mission in 1804, provides mapping support and intelligence for the Defense Department. It was housed in several downtown buildings before moving to the Arsenal complex in 1952. The Air Force, the agency that operates the Arsenal, hasn’t said what it will do with the current site, which houses several historic buildings.

Susan Pollman, the programming director for NGA’s new western campus, said the city’s location fit well with the agency’s mission, particularly with retention and recruitment of new employees.

“We are an analytical agency, and our director is an analyst,” Pollman said.