Under the son and successor of Frederick Barbarossa, Henry VI, the Hohenstaufen dynasty reached its apex. Henry added the Norman kingdom of Sicily to his domains, held English king Richard the Lionheart captive, and aimed to establish a hereditary monarchy when he died in 1197.
On April 15, Lincoln called on the states to send detachments totaling 75,000 troops to recapture forts, protect Washington, and "preserve the Union", which, in his view, remained intact despite the seceding states. This call forced states to choose sides. Virginia seceded and was rewarded with the designation of Richmond as the Confederate capital, despite its exposure to Union lines. North Carolina, Tennessee, and Arkansas followed over the following two months. Secession sentiment was strong in Missouri and Maryland, but did not prevail; Kentucky remained neutral. The Fort Sumter attack rallied Americans north of the Mason-Dixon line to defend the nation.
When Kun became aware of Romanian preparations for an offensive, he fortified mountain passes in the territory controlled by the Hungarian Army. Then, on the night of 15–16 April, the Hungarians launched a preemptive attack.
Luciano decided to eliminate Masseria (Lower Manhattan gang boss) . The war had been going poorly for Masseria, and Luciano saw an opportunity to switch allegiance. In a secret deal with Maranzano, Luciano agreed to engineer Masseria's death in return for receiving Masseria's rackets and becoming Maranzano's second-in-command. On April 15, Luciano invited Masseria and two other associates to lunch in a Coney Island restaurant. After finishing their meal, the mobsters decided to play cards. At that point, according to mob legend, Luciano went to the bathroom. Four gunmen then walked into the dining room and shot and killed Masseria.
In early March, in an attempt to protect its last oil reserves in Hungary and to retake Budapest, Germany launched its last major offensive against Soviet troops near Lake Balaton. In two weeks, the offensive had been repulsed. The operation lasted from 6 to 16 March, while the Soviet counter attack took place between 16 March to 15 April 1945.
During the night of 14/15 April, a diversionary landing was planned near Baracoa, Oriente Province, by about 164 Cuban exiles commanded by Higinio 'Nino' Diaz.The reconnaissance boats turned back to the ship after their crews detected activities by Cuban militia forces along the coastline. As a result of those activities, at daybreak, a reconnaissance sortie over the Baracoa area was launched from Santiago de Cuba. That was a FAR (Fuerza Aérea Revolucionaria) (Cuban Air Force) T-33, piloted by Lt Orestes Acosta, and it crashed fatally into the sea.
About 90 minutes after the eight B-26s had taken off from Puerto Cabezas to attack Cuban airfields, another B-26 departed on a deception flight that took it close to Cuba but headed north towards Florida. Like the bomber groups, it carried false FAR markings and the same number 933 as painted on at least two of the others. Before departure, the cowling from one of the aircraft's two engines was removed by CIA personnel, fired upon, then re-installed to give the false appearance that the aircraft had taken ground fire at some point during its flight. At a safe distance north of Cuba, the pilot feathered the engine with the pre-installed bullet holes in the cowling, radioed a mayday call, and requested immediate permission to land at Miami International airport. He landed and taxied to the military area of the airport near an Air Force C-47 and was met by several government cars. The pilot was Mario Zúñiga, formerly of the FAEC (Cuban Air Force under Batista), and after landing, he masqueraded as 'Juan Garcia' and publicly claimed that three colleagues had also defected from the FAR.
On April 15,The Cuban national police, led by Efigenio Ameijeiras, started the process of arresting thousands of suspected anti-revolutionary individuals, and detaining them in provisional locations such as the Karl Marx Theatre, the moat of Fortaleza de la Cabana and the Principe Castle all in Havana, and the baseball park in Matanzas.
The Palm Sunday massacre was a 1984 mass-murder in Brooklyn, New York, that resulted in the deaths of ten people: two women, two teenage girls, and six children. There was one survivor, an infant girl. All of the victims were shot, with a total of 19 bullets fired from two handguns at close range, most in the head, and were found in relaxed poses sitting in couches and chairs, suggesting that they had been taken by surprise.
When the gates were opened, thousands of fans entered a narrow tunnel leading from the rear of the terrace into two overcrowded central pens (pens 3 and 4), creating pressure at the front. Hundreds of people were pressed against one another and the fencing by the weight of the crowd behind them.
When Hu Yaobang suddenly died of a heart attack on 15 April 1989, students reacted strongly, most of them believing that his death was related to his forced resignation. Hu's death provided the initial impetus for students to gather in large numbers.
Small spontaneous gatherings to mourn Hu began on 15 April around Monument to the People's Heroes at Tiananmen Square. On the same day, many students at Peking University (PKU) and Tsinghua University erected shrines, and joined the gathering in Tiananmen Square in a piecemeal fashion.
From 1983 to 1997, Hong Kong saw an exodus of emigrants to overseas countries, especially in the wake of the 1989 Tiananmen Square crackdown, which more than a million Hongkongers showed up on the streets to support to student protesters in Beijing. The Tiananmen incident of 1989 strengthened anti-Beijing sentiments and also led to the emergence of the local democracy movement, which demanded a faster pace of democratisation before and after 1997.
As is common at domestic matches in England, opposing supporters were segregated. Nottingham Forest supporters were allocated the South Stands and Spion Kop on the east end, with a combined capacity of 29,800, reached by 60 turnstiles spaced along two sides of the ground. Liverpool supporters were allocated the North and West ends (Leppings Lane), holding 24,256 fans, reached by 23 turnstiles from a narrow concourse. Turnstiles numbered 1 to 10, 10 in all, provided access to 9,700 seats in the North Stand; a further 6 turnstiles provided access to 4,456 seats in the upper tier of the West Stand. Finally, 7 turnstiles (lettered A to G) provided access to 10,100 standing places in the lower tier of the West Stand. Although Liverpool had more supporters, Nottingham Forest was allocated the larger area, to avoid the approach routes of rival fans crossing. As a result of the stadium layout and segregation policy, turnstiles that would normally have been used to enter the North Stand from the east were off-limits and all Liverpool supporters had to converge on a single entrance at Leppings Lane. On match day, radio and television advised fans without tickets not to attend. Rather than establishing crowd safety as the priority, clubs, local authorities and the police viewed their roles and responsibilities through the 'lens of hooliganism'.
The crowd in the Leppings Lane Stand overspilled onto the pitch, where the many injured and traumatised fans who had climbed to safety congregated.
The agreed upon protocol for the South Yorkshire Metropolitan Ambulance Service (SYMAS) was that ambulances were to queue at the entrance to the gymnasium, termed the casualty reception point, or CRP.
The system of ferrying injured from any location within the stadium to the CRP required a formal declaration to be made by those in charge for it to take effect. As this declaration was not immediately performed, confusion reigned over those attempting to administer aid on the pitch. This confusion migrated to the first responders waiting in ambulances at the CRP, a location which quickly deteriorated into an ambulance parking lot. Some crews were hesitant to leave their vehicles, unsure of whether patients were coming to them, or vice versa.
A total of 42 ambulances arrived at the stadium. Out of this number, two managed of their own accord to make their way onto the pitch — while a third ambulance made its way onto the pitch at the direction of DCAO Hopkins, who felt its visibility might allay crowd concerns. The remaining 39 ambulances were collectively able to transport approximately 149 people to either Northern General Hospital, Royal Hallamshire Hospital, or Barnsley Hospital for treatment.
A total of 96 people died as a result of injuries incurred during the disaster. Ninety-four persons, aged from 10 to 67 years old, died on the day, either at the stadium, in the ambulances, or shortly after arrival at hospital. A total of 766 people were reported to have suffered injuries, although less than half required hospital treatment. The less seriously injured survivors who did not live in the Sheffield area were advised to seek treatment for their injuries at hospitals nearer to their homes.
The April incidents escalated into an armed conflict on 15 April in the area of Vitez, Busovača, Kiseljak and Zenica. The outnumbered HVO in the Zenica municipality was quickly defeated, followed by a large exodus of Croat civilians.
On April 15, 2013, Facebook announced an alliance across 19 states with the National Association of Attorneys General, to provide teenagers and parents with information on tools to manage social networking profiles.
In March 2020, the restaurant announced that it would be closing all its stores temporarily, in response to lockdown measures during the COVID-19 outbreak. On 15 April 2020, the store announced it would be reopening some stores for delivery services, as well as donating free meals to the NHS.
The SUD (trade unions) brought a court case against Amazon for unsafe working conditions. This resulted in a French district court (Nanterre) ruling on April 15, 2020, ordering the company to limit its deliveries to food and essential medical or hygienic products or pay a €1 million per day fine. Amazon said it would appeal, and on the following day shut its six French warehouses until at least April 21, 2020, for evaluation of the situation.