List of Governors of Illinois

The Governor of Illinois is the head of the executive branch of Illinois's state government and the commander-in-chief of the state's military forces. The governor has a duty to enforce state laws and the power to either approve or veto bills passed by the Illinois Legislature, to convene the legislature, and to grant pardons. Governors and other statewide officials are chosen to four-year terms in the off-year cycle (not in the same year as the presidential elections).

Illinois Territory was formed on March 1, 1809, from Indiana Territory. It had only one governor appointed by the President of the United States before it became a state. From March to June, 1809, Territorial Secretary Nathaniel Pope served as acting governor; Edwards' arrival in Illinois ended Pope's brief administration.

Illinois was admitted to the Union on December 3, 1818, consisting of the southern portion of Illinois Territory; the remainder was assigned to Michigan Territory.

The first Illinois Constitution, ratified in 1818, provided that a governor be elected every four years for a term starting on the first Monday in the December following an election. The constitution of 1848 moved the start of the term to the second Monday in January. Governors were not allowed to succeed themselves until the 1870 constitution, which removed this limit.

The office of lieutenant governor was created in the first constitution, to exercise the power of governor if that office becomes vacant. The 1848 constitution changed this to say the power "devolves" upon the lieutenant governor in case of a vacancy. The current constitution of 1970 made it so that, in the event of a vacancy, the lieutenant becomes governor, and the governor and lieutenant governor are now elected on the same ticket.

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