Complex sentence: Consequently, he decided to switch from federal to state politics: he was appointed Minister President of the state of Baden-Württemberg on 17 December 1958, an office in which he served until 1 December 1966.
Split into simpler sentences: Consequently, he decided to switch from federal to state politics. Kiesinger became Minister President of the state of Baden-Württemberg on 17 December 1958, an office in which he served until 1 December 1966.