Jacob Johan Anckarström (May11, 1762- April 27, 1792) was a Swedish military officer who was convicted and executed for regicide. On March 16, 1792 Anckarström shot the king in the masquerade ball at the Royal Opera. In the same year, the Anckarström´s changed their surname to Löwenström and donated funds for a hospital as a gift of appeasement.
This resulted in the Löwenström hospital, or Löwenströmska sjuk- huset.Anckarström was arrested the following morning and immediately confessed to the murder, Anckarström was jailed in our old former prison..

Gustav III died of his wounds on March 29, and on April 16, Anckarström was sentenced. He was stripped of his estates and nobility privileges. He was sentenced to be cast in irons for three days and flogged, and his right hand was to be cut off before he was decapitated. The execution took place on April 27, 1792. Why did he kill the king? When Gustav III became a king he carried out a lenient war 1772 with financial aid from France and he altered the constitution in order for him to gain more power.

He prohibited for example death penalty for some crimes and he reformed a law to give people permission to have any religion.
The end of 1780 Sweden declared war with Russia and Finland. Denmark declared war with Sweden. Gustav III failed the wars, which ensued to the officers turning against Gustav III.

The officers handled the peace negotiations without Gustav III. Most of the officers were the nobility, and the king accused the nobles for treachery, hence he turned the other social classes against the nobility and with the help from the other social classes he became an absolute ruler of the country.

Eventually, Sweden called a truce with Russia, Finland and Denmark. Sweden had a lot of issues; a lot of people hated the king and they deemed he was a tyrant. Roused by the French Revolution, people saw the possibilities to rebel. A conspiracy was planned and accomplished on March 16th in the masquerade ball at Kungliga Operan in Stockholm, Gustav was shot by a noble man called Jacob Johan Anckarström. Two weeks later the king died from bloodpoisoning.