The Library and Archives Canada has placed the Census of Manitoba, 1870 online. According to its news blurb of July 11, 02013,
This census was taken shortly after Manitoba joined Confederation.You can search the census by keywords, surname, given names and age.
This census provides the names of more than 12,200 individuals living in Manitoba at that time and contains information such as age, marital status, place of birth, religion, race and name of the father.