Republic of Formosa
The Republic of Formosa (), was a short-lived republic that existed on the island of Taiwan in 1895 between the formal cession of Taiwan by the Qing Dynasty of China to the Empire of Japan by the Treaty of Shimonoseki and it being taken over by Japanese troops. The Republic was proclaimed on 23 May 1895 and extinguished on 21 October, when the Republican capital Tainan was taken over by the Japanese. Though sometimes claimed as the first Asian republic to have been proclaimed, it was predated by the Lanfang Republic in Borneo, established in 1777, as well as by the Republic of Ezo in Japan, established in 1869.
Republic of Sonora
The Republic of Sonora was a short-lived, unrecognized federal republic ruled by filibuster William Walker in 1854. It was based in Baja California, which also claimed (but never controlled) Sonora. Walker's exploits generated interest back in San Francisco, where bonds for the Republic of Sonora were sold and its flag was even raised in places. His enterprise however suffered from a lack of supplies, discontent from within, and resistance by the Mexican government quickly forced Walker to retreat.