Carl Johan Thyselius (8 June 1811 – 11 January 1891) was a politician, state official (Swedish: ämbetsman), Justice Councillor (Swedish: justitieråd) 1856-60, "Minister for Ecclesiastical Affairs" (comparable to Minister of Education, Swedish: ecklesiastikminister) 1860-63, Minister for Civil Affairs (responsible for trade, industry and ship transport; Swedish: civilminister) 1875-80, and served as Prime Minister from 1883 to 1884.At the age of 72 years and 5 days, Thyselius is the oldest person to become Prime Minister in Swedish history.
In 1848 he married Charlotta Melart with whom he had a daughter.