Complex sentence: The Provincial Secretary was the equivalent of the former Canadian Cabinet position of Secretary of State for Canada in that it included an eclectic variety of responsibilities, most of which would eventually evolve into portfolios of their own.
Split into simpler sentences: The Provincial Secretary was the equivalent of the former Canadian Cabinet position of Secretary of State for Canada. Like its federal counterpart it included an eclectic variety of responsibilities, most of which would eventually evolve into portfolios of their own.