| 775 | First documentary mention of the “villa gotaha” in a deed of gift to the Hersfeld Abbey signed by Charlemagne |
| 1180/89 | First documentary mention of Gotha as a town |
| 1247 | Transition of sovereignty from the Thuringian Landgraves to the Wettins |
| 1515 | The reformer Martin Luther (1483-1546) preaches for the first time in Gotha (last time in 1537) |
| 1524 | On Luther's recommendation, Myconius (1490-1546) is called to Gotha as the first Protestant preacher and superintendent |
| 1566 | Siege of the city of Gotha by a superior imperial execution army under Elector August of Saxony (Grumbach Feud) |
| 1567 | Surrender to the imperial troops, capture of Grumbach and public execution of the outlaws on the main market |
| 1640 | Estate division of the Ernestine duchies and establishment of the duchy Saxe-Gotha under duke Ernest I, called "Ernest The Pious”; Gotha becomes seat of the duchy (until 1918) |
| 1753 | Stay of the French philosopher and writer Voltaire (1694-1778) at Friedenstein Palace |
| 1825 | Extinction of the house of Saxe-Gotha-Altenburg |
| 1826 | Creation of the duchy Saxe-Coburg and Gotha |
| 1847 | Opening of the Erfurt-Gotha and Gotha-Eisenach railway lines |
| 1894 | Opening of the first electric tramway |
| 1918 | The Worker's and Soldier's Council of Gotha deposes Charles Edward as Duke of Saxe-Coburg and Gotha; the duchy becomes the Free State of Saxe-Gotha (until 1920) |
| 1920 | Kapp Putsch in March: armed workers' army fighting Reichswehr troops;formation of the State of Thuringia from the 7 former duchies and principalities |
| 1945 | Liberation of Gotha by the 4th armoured division of the Third United States Army on the 4th of April;Change of occupying powers in Gotha (arrival of the Red Army on the 3rd of July) |
| 1989 | Prayers for peace in the Church of St. Augustine followed by demonstrations;resignation of the Gotha city council;political discussions at the "round table" at the invitation of the Protestant Church |
| 1990 | first free democratic local elections after 1946 |
| 1994 | Gotha receives the status “Große kreisangehörige Stadt” (large district city) |
