article: List of countries in the 1820s
links: Sikkim Saxe-Altenburg Duchy of Nassau Joseon Saxe-Coburg-Gotha Hohenzollern-Hechingen Konbaung dynasty Grand Duchy of Oldenburg Saxe-Gotha-Altenburg Grand Duchy of Tuscany Qajar Iran Confederation of the Equator Kingdom of Portugal Saxe-Meiningen Perak Qing dynasty Saxe-Coburg-Saalfeld Kingdom of Kongo Saxe-Hildburghausen Nguyễn dynasty Bourbon Restoration in France First Mexican Republic Peru Emirate of Bukhara Kingdom of Nepal Russian Empire List of sovereign states in the 1830s Durrani Empire Kingdom of Denmark Hohenzollern-Sigmaringen First Mexican Empire Moldavia Samoa Kingdom of Koya Federal Republic of Central America Sikh Empire Tokugawa shogunate Saxe-Weimar-Eisenach Grand Duchy of Hesse Gran Colombia Bornu Empire Kingdom of Hawaii Union between Sweden and Norway Pahang Fiji Grand Duchy of Baden Dahomey Rattanakosin Kingdom (1782–1932) Selangor