- Jan 1 African Benevolent Society (education) forms
- Jan 1 Congress prohibits importation of slaves
- Jan 1 Sierra Leone becomes a British colony
- Jan 10 Herman Daendels succeeds Albertus Wiese as Governor-General of Dutch-East Indies
- Jan 12 The organizational meeting that led to the creation of the Wernerian Natural History Society, a former Scottish learned society, is held in Edinburgh.
- Jan 19 Louis Napoleon signs 1st Dutch aviation law
- Jan 26 Rum Rebellion, the only successful (albeit short-lived) armed takeover of the government in Australia
- Feb 11 Anthracite coal 1st burned as fuel, experimentally, Wilkes-Barre, Pennsylvania
- Feb 21 Russia invades Finland, then part of the Swedish Kingdom, with 24,000 troops
- Mar 2 The inaugural meeting of the Wernerian Natural History Society, a former Scottish learned society, was held in Edinburgh.
- Mar 7 Portugal's regent Dom Juan IV arrives in Rio De Janeiro
Event of Interest
Mar 19 Charles IV, king of Spain, abdicates after riots and a popular revolt at the winter palace Aranjuez. His son, Ferdinand VII, takes the throne
- Mar 26 Charles IV of Spain abdicates in favor of his son, Ferdinand VII
- Mar 31 French created Kingdom of Westphalia orders Jews to adopt family names
The Third of May 1808
May 3 Day depicted by Spanish painter Goya in his "The Third of May", painted 1814
- May 3 Finnish War: Sweden loses the fortress of Sveaborg to Russia
- May 3 Peninsular War: The Madrid rebels who rose up on May 2 are fired upon near Príncipe Pío hill
- May 30 Napoleon Bonaparte annexes Tuscany & gave it seats in French Senate
- Jun 1 1st US land-grant university founded as Ohio University in Athens, Ohio
- Jun 15 Joseph Bonaparte becomes King of Spain
- Jul 2 Simon Fraser completes his trip down Fraser River, British Columbia, lands at Musqueam
- Jul 15 French marshal Joachim Murat becomes King of Naples
- Jul 20 Napoleon decrees all French Jews adopt family names
Victory in Battle
Aug 21 Battle of Vimeiro: British and Portuguese forces led by General Arthur Wellesley defeat French force under Major-General Jean-Andoche Junot near the village of Vimeiro, Portugal, the first Anglo-Portuguese victory of the Peninsular War.
- Sep 13 Finnish War: In the Battle of Jutas, Swedish forces under Lieutenant General Georg Carl von Döbeln beat the Russians, making von Döbeln a Swedish war hero.
- Sep 30 Covent Garden Theatre Royal destroyed by fire in London
- Oct 17 Political rights of Jews suspended in Duchy of Warsaw
- Oct 31 Holland Brigade battle at Durango, Spain
- Nov 10 Osage Treaty / Treaty of Fort Clark, Osage Nation cedes territory in Missouri and Arkansas to the US