Emperor Diocletian declared Milan as the capital of the Western Roman Empire.
Celtic Insubres inhabited Milan
- 400 BC - Celtic Insubres inhabited Milan
- 222 BC - Romans conquered the city and named it Mediolanum
- 293 - Emperor Diocletian declared Milan as the capital of the Western Roman Empire.
- 313 - The Emperor Constantine I, with the Edict of Milan, guaranteed freedom of Christianity.
- 402 - Visigoths attacked the city and Ravenna became the imperial residence.
- 539 - Ostrogoths destroyed the city during Gothic War against Byzantine Emperor Justinian I.
- 774 - Franks invaded Milan and Charlemagne took the title King of the Lombards.
- 1162 - Frederick I Barbarossa conquered and destroyed Milan.
- 1167 - Foundation of the Lombard League.
- 1183 - With the Peace of Constance Milan became duchy.
- 1395 - Gian Galeazzo Visconti became the duke of Milan.
- 1447 - Filippo Maria Visconti died without a male heir which ended the Visconti line and the Ambrosian Republic was re-established.
- 1450 - Francesco Sforza conquered Milan.
- 1492 - The French King Louis XII laid claim to the duchy.
- 1525 - Northern Italy, including Milan, passed to the House of Habsburg with the Battle of Pavia.
- 1700 - The Spanish line of Habsburg ended with the death of Charles II.
- 1701 - The War of Spanish Succession began.
- 1706 - The French were defeated and forced to yield northern Italy to the Austrian Habsburgs.
- 1713 - With the Treaty of Utrecht most of Spain's Italian possessions left to Austrians.
- 1796 - Napoleon conquered Lombardy and Milan became the capital of the Cisalpine Republic.
- 1815 - The Congress of Vienna returned Lombardy and Milan and Veneto to Austrian control.
- 1848 - The Milanese rebelled against Austrians.
- 1859 - Austria was defeated at the Battle of Solferino by Sardinia and France union.
- 1919 - Benito Mussolini formed the core of Italy's Fascist Movement in Milan.
- 1944 - During World War II Germans occupied most of northern Italy until 1945.
- 1945 - Fascists were hung in Milan at Piazzale loreto.
- 1950 - Immigration to Milan rapidly increased by 1960s to seek jobs.
