On 21 March, Béla Kun led a successful communist coup d'état. Károlyi was deposed and arrested. Kun formed a social democratic, communist coalition government and proclaimed the Hungarian Soviet Republic. Days later the Communists purged the Social Democrats from the government.
On 21 March 1933, the new Reichstag was constituted with an opening ceremony at the Garrison Church in Potsdam. This "Day of Potsdam" was held to demonstrate unity between the Nazi movement and the old Prussian elite and military. Hitler appeared in a morning coat and humbly greeted Hindenburg.
The Battle of Hill Eerie refers to several Korean War engagements between the United Nations Command (UN) forces and the Chinese People's Volunteer Army (PVA) in 1952 at Hill Eerie, a military outpost about 10 miles (16 km) west of Ch'orwon. It was taken several times by both sides; each sabotaging the others' position.
Because the penitentiary cost much more to operate than other prisons (nearly $10 per prisoner per day, as opposed to $3 per prisoner per day at Atlanta), and half a century of saltwater saturation had severely eroded the buildings, then-Attorney General Robert F. Kennedy ordered the penitentiary closed on March 21, 1963.
Iran's next major offensive, led by then Colonel Ali Sayad Shirazi , was Operation Fath-ol-Mobeen (Undeniable Victory). On 22 March 1982, Iran launched an attack which took the Iraqi forces by surprise: using Chinook helicopters, they landed behind Iraqi lines, silenced their artillery, and captured an Iraqi headquarters. The Iranian Basij then launched "human wave" attacks, consisting of 1,000 fighters per wave. Though they took heavy losses, they eventually broke through Iraqi lines. Operation Undeniable Victory was an Iranian victory; Iraqi forces were driven away from Shush, Dezful and Ahvaz. The Iranian armed forces destroyed 320–400 Iraqi tanks and armored vehicles in a costly success.
Saddam responded by launching chemical attacks against the Iranian positions along the highway and by initiating the second "war of the cities", with an air and missile campaign against twenty to thirty Iranian population centers, including Tehran.
On 21 March 2019, May presented her case to a European Council summit meeting in Brussels. After May left the meeting, a discussion amongst the remaining EU leaders resulted in the rejection of 30 June date and offered instead a choice of two new alternative Brexit dates.