He was first elected to Vancouver City Council in 1959 as a member of the Non-Partisan Association, a civic political party.
In 1962, Rathie wrested the NPA nomination from incumbent mayor Thomas Alsbury, and was elected to succeed him in that office.
Vancouver in the mid-sixties was enjoying spectacular growth in its economy and population, and was well on its way to becoming a major international city.
During his tenure, a 20-year programme for Vancouver's redevelopment, encompassing transportation, low-cost housing, and downtown revitalization was outlined.
Its scope and orientation would lead to controversy and protest following Rathie's term of office.