Sentence:  On Big Stone Lake near the headwaters of the Red River , Robert Dickson , Superintendent of the <WSD>Western</WSD> Indian Department of Canada , had a trading post and planned in 1818 to build a fort to be defended by twenty men and two small artillery pieces . 
Meaning of the word marked with <WSD> tags:  relating to or characteristic of the western parts of the world or the West as opposed to the eastern or oriental parts