Zhangzhou fu (漳州府) was a prefecture in Fujian Province in China's imperial and early republican eras. The region, especially its governmental/commercial centre, was long known to English-readers accustomed to Wade-Giles romanisation as Changchow fu.
The region has since been reconstituted as Zhangzhou Prefecture-level city.
References
Zhangzhou fu Wikipedia(Text) CC BY-SA