He studied law at the University of Tübingen, obtaining a doctoral degree in 1957 with a dissertation titled Die Reformbedürftigkeit des Bundesverfassungsgerichts (The necessity of reform of the Federal Constitutional Court) and passing the state examination in 1959.
He was the 9th President of the Bundestag from 1984 to 1988. In 1960, he started working in the Bundeswehr administration in Stuttgart. He became an assistant in the Federal Ministry of Defense and later personal assistant and press contact of Federal Minister for the Affairs of the Defence Council Heinrich Krone.
After the dissolution of this ministry, he worked from 1966 to 1969 as political assistant of Federal Minister of Finance Franz Josef Strauß.
Between 1982 and 1984, Jenninger served as Minister of State at the German Chancellery, under Chancellor Helmut Kohl. At first, he represented Crailsheim.
After 1976, he represented Schwäbisch Hall. After Rainer Barzel"s resignation, Jenninger was elected President of the Bundestag on 5 November 1984.
As President, he made a controversial speech in a special session on 10 November 1988 commemorating the 50th anniversary of Kristallnacht.
His speech was presented badly (by his own later admission), as his way of speaking allowed the interpretation that Jenninger didn"t sufficiently dissociate himself from the Nazi ideas he referred to, making it hard to distinguish what were his own ideas and what were the "fascinating" (as Jenninger said) Nazi ideas he was just reporting. This caused a political storm, and Jenninger resigned his Bundestag presidency on 11 November. He did not stand for reelection as a Bundestag member in the 1990 elections.
One year after the incident, Jewish community leader Ignatz Bubis, who later became chairman of the Central Council of Jews in Germany, used several passages of Jenninger"s speech verbatim (although he didn"t use the word "fascinating"), demonstrating that the content of Jenninger"s speech had not been wrong, just his performance of lieutenant
Jenninger served as German ambassador to Vienna, Austria from 1991 to 1995, and as ambassador to the Holy See from 1995 to 1997. Phillipp Jenninger was President of the European Movement in Germany from 1985 to 1990, and has since been their honorary President.
Jenninger tried to explain the reasons behind German enthusiasm for National Socialism in the 1930s.
European Academy of Sciences and Arts]
He also served as Member of the German Parliament, the Bundestag (1969–1990), Minister of State at the German Chancellery (1982–1984),, German Ambassador to Austria (1991–1995) and German Ambassador to the Holy See (1995–1997). Jenninger was a member of the Bundestag from 1969 to 1990, always as directly elected representant of a constituency. More than 50 members of parliament walked out during their President"s speech in protest.
He is a member of the presidium of Studienzentrum Weikersheim.