| 29 March 991 | France [political events] | Bishop Asselin of Laon captures Duke Charles of Lower Lorraine, the pretender to the French throne, and Archbishop Arnulf of Reims on King Hugh of France's behalf, so ending Charles's attempt to win the throne of France. |
| 29 March 1550 | England, France, Scotland [treaties] | By the Peace of Boulogne, England returns the northern French port of Boulogne to France four years earlier than specified in the 1546 Peace of Ardres, for 400,000 crowns, and withdraws from Scotland; King Henry II of France, now free to oppose the Holy Roman Emperor Charles V, has a free hand there. |
| 29 March 1792 | Sweden [revolution] | King Gustav III of Sweden is assassinated in the course of an aristocratic coup. |
| 29 March 1809 | Sweden [wars] | King Gustavus IV Adolphus of Sweden is forced to abdicate after military defeats in war with Denmark. |
| 29 March 1849 | India, UK [treaties] | Britain annexes the Indian province of Punjab by a treaty with the maharajah of Lahore, following the surrender of the Sikh army on 12 March. |
| 29 March 1867 | UK, Canada [legislation] | The British North America Act establishes the Dominion of Canada comprising Quebec, Ontario, Nova Scotia, and New Brunswick, confederated provinces with a central parliamentary government under a British governor-general. |
| 29 March 1927 | USA, UK [speed records] | The British driver Henry Segrave establishes a new world land-speed record of 327.96 kph/203.79 mph in a 1,000 hp Sunbeam, at Daytona Beach, Florida. He is the first person to set a land-speed record in excess of 200 mph. |
| 29 March–6 April 1932 | Palestine [Judaism] | Jewish athletes from 20 countries participate in the inaugural World Maccabiah Games in Tel Aviv. |
| 29 March 1964 | UK [radio] | Radio Caroline, the first offshore ‘pirate’ radio station broadcasting to Britain, begins transmissions from a ship in the North Sea. Modelled on Radio Luxembourg with its nonstop diet of pop music, it is Britain's first pop music station. |
| 29 March 1972 | North Vietnam, South Vietnam [Vietnam War (1954–75)] | The North Vietnamese launch a major offensive in the Vietnam War in Quang Tri, South Vietnam's northernmost city. |
| 29 March 1979 | USA [energy] | Radioactive material escapes from the nuclear power station at Three Mile Island, Pennsylvania, when the reactor overheats. Fearing a meltdown and the release of radioactive caesium, 144,000 people are evacuated from the immediate area. The accident halts the growing trend towards reliance on nuclear energy in the USA; 11 orders for new reactors are immediately cancelled, with more cancelled the following year. |
| 29 March 1983 | USA [computing] | The Tandy Corporation markets the first laptop computer in the USA. The TRS-80 Model 100 weighs less than 2 kg/4 lb and runs on 4 small batteries; prices range from $799 to $999. |
| 29 March 2004 | Ireland [public health] | The Republic of Ireland becomes the first country in the world to introduce a nationwide ban on smoking in every workplace. |
| 29 March 2004 | [international organizations] | The North Atlantic Treaty Organization (NATO) welcomes seven new members, as Bulgaria, Estonia, Latvia, Lithuania, Romania, Slovakia, and Slovenia formally join the western political and military alliance. Their accession brings the total membership of NATO to 26 countries. |
