- Iceland: Archontology
- Iceland: Heads of State: 1918-1944
- Iceland: Heads of State: 1944-2024
- Iceland: Official Gazette 1944
- Iceland: Polity Style: 1918-2024
- Iceland: Regents: 1940-1944
- Iceland: Sources
- Ignatov, Nikolaj
- India: Archontology
- India: Glossary
- India: Governors-General: 1947-1950
- India: Heads of State: 1947-1950
- India: Heads of State: 1950-2024
- India: Polity Style: 1947-2024
- Indonesia: Archontology
- Indonesia: Glossary
- Indonesia: Heads of State: 1950-2024
- Indonesia: Notes
- Indonesia: Polity Style: 1950-2024
- Ionian Islands: Archontology
- Ionian Islands: Lords High Commissioners: 1816-1864
- Ionian Islands: Notes
- Ionian Islands: Polity Style: 1816-1864
- Ionian Islands: Presidents of the Senate: 1817-1864
- Ionian Islands: Sources
- Iran: Archontology
- Iran: Heads of Provisional Government: 1925
- Iran: Leaders: 1979-2024
- Iran: Polity Style: 1979-2024
- Iran: Presidents of the Republic: 1979-2024
- Iran: Rulers: 1796-1925
- Iran: Rulers: 1925-1979
- Iran: Sources
- Iraq: Archontology
- Iraq: Head of Government: 1920-1921
- Iraq: Heads of State: 1958-2003
- Iraq: Heads of State: 2004-2024
- Iraq: Kings: 1921-1958
- Iraq: Military Occupation: 2003-2004
- Iraq: Polity Style: 1920-2024
- Iraq: Sources
- Ireland: Archontology
- Ireland: Chairmen of the Provisional Government: 1922
- Ireland: Dáil Éireann: 1919
- Ireland: Executive Authority and External Relations: 1936-1949
- Ireland: Heads of Government: 1922-2024
- Ireland: Heads of State: 1922-1937
- Ireland: Heads of State: 1937-2024
- Ireland: Polity Style: 1919-2024
- Ireland: Presidential Commission: 1937-1938
- Ireland: Presidential Commission: 1974
- Ireland: Presidential Commission: 1976
- Ireland: Presidential Commission: 1997
- Ireland: Presidential Elections
- Ireland: Presidents of Dáil Éireann: 1919-1922
- Ireland: Sources
- Ireland: Vacancy in the Office of President of Dáil Éireann: 1922
- Irish Free State: Governors-General: 1922-1936
- Isabel (princess, regent of Brazil)
- Isabel II
- Islamic State of Indonesia: Archontology
- Islamic State of Indonesia: Heads of State: 1949-1962
- Islamic State of Indonesia: Polity Style: 1949-1962
- Isnard, Maximin
- Israel: Archontology
- Israel: Head of the Provisional Council of State: 1948-1949
- Israel: Head of the Provisional Government: 1948-1949
- Israel: Heads of State: 1949-2024
- Israel: Polity Style: 1948-2024
- Israel: Provisional Authorities: 1948-1949
- Israel: Sources
- Italian Republic: Archontology
- Italian Republic: Heads of State: 1802-1805
- Italian Republic: Polity Style: 1802-1805
- Italian Republic: Sources
- Italian Social Republic: Archontology
- Italian Social Republic: Heads of State: 1943-1945
- Italian Social Republic: Polity Style: 1943-1945
- Italian Social Republic: Sources
- Italy (Kingdom of): Sources
- Italy: Archontology
- Italy: Heads of State: 1946-2024
- Italy: Kings: 1861-1946
- Italy: Polity Style: 1861-2024
- Italy: Sources
Last update: 21 Nov 2024