October 1841 sees the British solidify their…
October 1841 CE
Chusan had been exchanged for Hong Kong on the authority of Qishan in January 1841, after which the island had been re-garrisoned by the Qing.
Fearing that the Chinese will improve the island's defenses, the British capture Chusan for a second time on October 1 and reestablished their control over Dinghai's important harbor.