List of state leaders in 1803
Africa
- Akwa Akpa – Ekpenyong Offiong Okoho, King of Akwa Akpa
- Ashanti Confederacy –
- # Osei Kwame Panyin, Asantehene
- # Osei Fofie, Asantehene
- Kingdom of Buganda – Semakokiro
- Bunyoro – Kyebambe III, Omukama of Bunyoro
- Kingdom of Burundi – Ntare IV Rugamba
- Kingdom of Dahomey – Adandozan
- Kingdom of Kaffa - Hoti Gaocho
- Ethiopian Empire – Egwale Seyon Hezqeyas
- Sultanate of Ndzuwani – Alawi bin Husain
- Kingdom of Rwanda – Yuhi III
- Zulu – Senzangakona, King of the Zulu
Asia
- Ahom kingdom -
- Alirajpur State - Pratap Singh I
- Burma - Bodawpaya
- Durrani Empire –
- # Mahmud Shah, King of Afghanistan
- # Shoja Shah, King of Afghanistan
- China - Jiaqing Emperor
- Empire of Japan
- *Monarch – Kōkaku
- *Tokugawa shogunate – Tokugawa Ienari
- *Ryukyu Kingdom – Shō Sei
- Khanate of Kokand – 'Alim Khan
- Joseon – Sunjo
- Kingdom of Luang Phrabang - Anurutha
- Sultanate of the Maldives – Mu'in ad-Din I Muhammad
- Nepal – Girvan Yuddha Bikram Shah, Maharajadhiraja of Nepal
- Siam – Rama I
- Sikh Empire – Ranjit Singh, Maharaja of the Sikh Empire
Europe
- Principality of Abkhazia – Kelesh Begi
- Andorra – Francesc Antoni de la Dueña y Cisneros, Bishop of Urgell
- Batavian Republic – Staatsbewind
- Kingdom of Denmark–Norway
- * Monarch – Christian VII
- * Minister of State - Christian Gunther
- Kingdom of Etruria –
- #Louis
- #Charles Louis
- French First Republic – Napoleon Bonaparte, First Consul
- Holy Roman Empire – Franz II
- Ottoman Empire
- * Sultan - Selim III
- *Grand Vizier – Yusuf Ziyaüddin Pasha
- Kingdom of Portugal and the Algarves –
- *Monarch – Maria I
- *Prince-Regent – Prince John
- Kingdom of Prussia – Frederick William III
- Russian Empire – Alexander I
- Kingdom of Spain – Charles IV
- Kingdom of Sweden – Gustav IV Adolf
- United Kingdom of Great Britain and Ireland
- * Monarch – George III
- * Prime Minister - Henry Addington
- Abu Dhabi – Shakhbut bin Dhiyab, Shaikh of Abu Dhabi
- Sultanate of Morocco – Slimane
- Persia – Fath Ali Shah
- Beylik of Tunis –
- * Bey - Hammuda ibn Ali
- * Grand Vizier – Yusuf Sahib al-Tabi
- United States - Thomas Jefferson, President of the United States
