In Vienna's Innere Stadt district, an ISIL sympathizer shoots and kills four people and injures 23 more, before being shot and killed by the police.

Vienna is the capital, most populous city, and one of nine states of Austria. It is Austria's primate city, with just over two million inhabitants. Its larger metropolitan area has a population of nearly 2.9 million, representing nearly one-third of the country's population. Vienna is the cultural, economic, and political center of the country, the fifth-largest city by population in the European Union, and the most populous of the cities on the river Danube.

The Innere Stadt is the 1st municipal district of Vienna located in the center of the Austrian capital. The Innere Stadt is the old town of Vienna. Until the city boundaries were expanded in 1850, the Innere Stadt was congruent with the city of Vienna. Traditionally it was divided into four quarters, which were designated after important town gates: Stubenviertel (northeast), Kärntner Viertel (southeast), Widmerviertel (southwest), Schottenviertel (northwest).

The Islamic State (IS), also known as the Islamic State of Iraq and the Levant (ISIL), the Islamic State of Iraq and Syria (ISIS) and Daesh, is a transnational Salafi jihadist militant organisation and was a unrecognised quasi-state. IS occupied significant territory in Iraq and Syria in 2013, but lost most of it in 2017 and 2019. In 2014, the group proclaimed itself to be a worldwide caliphate, and claimed religious and political authority over all Muslims worldwide, a claim not accepted by the vast majority of Muslims. It is designated as a terrorist organisation by the United Nations and many countries around the world, including Muslim countries.

On 2 November 2020, a series of shootings took place in Vienna, Austria a few hours before the city was scheduled to enter a lockdown as a result of the COVID-19 pandemic. A lone gunman started shooting in the busy city centre, killing four civilians and injuring 23 others, seven critically, including a police officer. The attacker was killed by police and was later identified as an ISIL sympathizer. Officials said that the attack was an incident of Islamist terrorism.