 After the 1959 election, the LSAP was replaced as the Christian Social People's Party's (CSV) coalition partner by the Democratic Party.Wilwertz was reappointed to the Council of State on 30 December 1959, and he remained until 16 December 1968, when he was re-elected to the Chamber of Deputies.He was elected Mayor of Luxembourg City in 1963, backed by a LSAP-CSV coalition, and held the office from 1964 until 1969.