Reker's mother was a life-long member of the SPD and moved to Cologne from Lower Silesia after World War II,[2] while her father was a pastry chef who lived in Vogelsang district his whole life.

Supported by the CDU, FDP, and The Greens, Reker ran for Mayor of Cologne in October 2015[6] and was re-elected in September 2020.

[7] At a public event on 17 October 2015, the day before the mayoral election, Reker was seriously wounded when a 44-year-old German man stabbed her in the neck with a knife,[8] while shouting about an "influx of refugees".

[9] Reker's main rival in the mayoral election, Social Democrat Jochen Ott, suspended his campaign after the attack.

[14][15] Reker was condemned by Lodewijk Asscher, Deputy Prime Minister of the Netherlands, for implying that women could have prevented the attacks against themselves.

[16] Reker accused the media of taking her comments out of context: she claimed that she had only reacted to a reporter's question by quoting an existing communal guideline for safety during partying in a speech.