Bill Rowling, who served as the 30th prime minister of New Zealand from 6 September 1974 to 12 December 1975, travelled internationally to attend bilateral and multilateral diplomatic meetings and to lead trade delegations. During his premiership, Rowling visited 11 sovereign countries. Background. Rowling appointed himself as Minister of Foreign Affairs with Joe Walding as an associate and focused on external matters for much of his premiership. Summary. The table below lists Rowling's international prime ministerial trips, all made in 1975: