Earlier Commissioners were mostly Deputy Ministers in various ministries (Minister of the Interior, Mines, Mines and Resources)).
As Commissioners are appointed by the Canadian federal government it is a misnomer to consider the office the Monarch's viceregal representative in the territory--that is, unlike in Canada's provinces, there is no such thing as a "territorial Crown" analogous to the provincial Crowns. The Commissioner must follow any instructions of the Cabinet or the relevant federal minister, currently the Minister of Aboriginal Affairs and Northern Development.
Since 1980, the territories have had self-government, with the legislature choosing a Government Leader or Premier, in addition to electing Members of Parliament to the Parliament of Canada.