Life and family
Coming from a liberal family, Kiep was born on 5 January 1926 in Hamburg to Louis Leisler Kiep, a navy captain and business man, and Eugenie Maria Anna vom Rath. Kiep's maternal grandfather, Walther vom Rath, had been a member of the Prussian House of Representatives from 1894 to 1898 and later a member of the Prussian House of Lords until 1918. His middle name "Leisler" came from Jacob Leisler, a German-born colonist and ancestor of Kiep, who participated in early independence movements in New York and was hanged by the English in 1691. Kiep went to school in Hamburg and Istanbul, achieving his Abitur in 1943 before joining the Wehrmacht. On 20 April 1944, Adolf Hitler's birthday, he joined the Nazi Party. In the same year his uncle, Otto Carl Kiep, was executed by the Nazis for his membership in the Kreisau Circle. After the war, he started to study history and economics, but did not graduate.
Before moving into politics, he worked for the Insurance Company of North America from 1948 to 1955. Starting in 1955, he worked for a company called Gradmann und Holler, an insurance broker company for large businesses. Kiep owned 15 percent of the company in 1982. His involvement with Gradmann und Holler sparked controversy. When Kiep became minister in Lower Saxony in 1976, Volkswagen and other local companies went into business with Gradmann und Holler, creating a possible conflict of interest for the minister. Kiep also served on Volkswagen's board of directors. Kiep denied abusing his power as minister, saying that the deal with Volkswagen had been financially damaging rather than profitable for his company. Due to his successful business ventures, Kiep was considered to be one of the richest politicians in Germany. In an interview, Kiep told Playboy that he could live well just from the interest from his savings.
From 1950, Kiep was married to Charlotte Kiep, born 1920, daughter of IG Farben board member and convicted war criminal Fritz ter Meer. They met when Kiep was only thirteen years old. He needed to visit Fritz ter Meer in Landsberg Prison to ask for his daughter's hand in marriage. They had four children together, sons Walther, Michael and daughters Charlotte and Christiane. Their second son, Michael Jürgen, died in 1975, aged 24. The parents started a foundation for young journalists in his name. From a previous marriage of his wife's, Kiep was stepfather to another son, Edmund.
On 30 November 1974, an assassination attempt was made on Kiep, during which a man fired three shots at the door of his sauna, though he remained uninjured. The assassin was never found and leads hinting towards involvement of the Red Army Faction proved inconclusive. As the German magazine Der Spiegel wrote a year later, some party colleagues allegedly considered it possible that Kiep had staged the attack himself.