The 《
战国策》 and the 《
史记》 first used the phrase for the Guanzhong plain, the Qin heartland around today's Xi'an.
诸葛亮 applied it to the Shu region in the
隆中对, and since then it has meant Sichuan. Chengdu now puts
天府 on everything from its main square to its new airport.