Austrian Chancellor Alexander Schallenberg said at the ceremony that terrorism "must not succeed in dividing us".
ADVERTISEMENTVienna has held a memorial event to commemorate victims on the first anniversary of a terrorist attack.
Austrian Chancellor Alexander Schallenberg, speaking at the ceremony, said that the attacker had failed to divide the country.
"Terrorism must not, will not succeed in dividing us ... it will not succeed in undermining the foundations of our free society," Schallenberg added on Tuesday.
The memorial event was held at St. Rupert's Church, near where the attack occurred in November 2020.
Austrian President Alexander Van der Bellen and the mayor of Vienna Michael Ludwig were also in attendance, alongside relatives of the victims.
Four people were killed and more than 20 injured, when a gunman rampaged through the streets of the Austrian capital.
The attacker -- a 20-year old Austrian-North Macedonian dual national with links to the so-called Islamic State -- was shot dead by police after nine minutes.
At least fifteen people have been arrested following the attack, with many still in custody.
Austrian authorities have been accused of misconduct after ignoring warnings about the attacker from Slovakia.
At the end of September, the government set up a compensation fund of €2.2 million euros for victims of terrorism.
But on the anniversary of the attack, victims' lawyers have demanded an apology from Austria for failures in the investigation.
"[There is] little comfort we can say to the relatives of the victims", Ludwig said in a statement.
There is no consolation, but there is a hand to comfort. We as a city government, as a municipal council, as a provincial parliament want to extend this hand to the relatives - as a sign of solidarity."
"We will not let ourselves be divided, Vienna has moved closer together and is stronger than ever," he added on Twitter.
"It was thanks to the quick action of the Vienna police that no more people lost their lives," Ludwig added.
"Vienna had demonstrated immense cohesion that night. People brought other people to safety without regard for their own lives, hid them in hotels, cinemas, and restaurants."
Chancellor Schallenberg also reiterated that the attack should not lead to anger against certain groups or religions.
"My thoughts today are with the victims and their families," added Austrian Interior Minister Karl Nehammer.
ADVERTISEMENT"The terrorist's aim was to divide our society, he did not succeed," Nehammer said on Twitter.
"Austria is a strong and mature democracy. We will continue to fight resolutely against extremism and terrorism."