Q: Mary Ann KERR, born in the Province of Quebec, married a William McINNES who had been born in Canada / English ~1865. William reportedly came down to US in ~1880 and settled in Somerville, MA. William and Mary married in MA ~1883. They seem to have had one child, a daughter, Mabel. They were still there in the 1920 ensus.
A: I see from the various census records (1900, 1910 and 1920) that William's age changes greatly. I wouldn't discard the earlier years of birth! 1900 shows June 1865. 1910 shows ca 1852 and 1920 shows ca 1853.
His immigration year also varies (not unusual as it is one of the most MISremembered years of all). Perhaps you can find him in 1880 US census or in 1871 census for Ontario (index only). If you are patient, Ancestry is bringing the Canadian 1861 and 1871 full census records online this year. See More Census Records Coming Online in 2009 for the full scoop on these records.
Q: .. he married Mary in MA ~1883, it was his 2nd marriage. And, if he came down ~1880, perhaps he had been married and widowed in Canada before he migrated down.
A: The 1910 census for William shows he has been married twice, and has been married to Mary for 27 years. There are many good clues in the various census years. You will see a list of questions for each census year for both USA and Canada census records on AllCensusRecords.com.
For example the 1910 census also shows that William naturalized in USA so you may want to have a hunt for his naturalization records.
Have you hunted for an earlier Canadian marriage for William? See ONTARIO VITAL STATS for help with this
Q: Also, in 1900, if someone was reported to have been born in "Canada English," would that be either the Maritime Provinces or Ontario Province? Or, would it just have been Nova Scotia or New Brunswick, etc.?
A: These terms found on Census records may be helpful to you inyour research:
CW or Can W = Canada West = present day Ontario
CE or Can E = Canada East = Quebec
UC = Upper Canada = Ontario
LC= Lower Canada=Quebec
Can - Eng = english speaking Canada- usually means Ontario but can refer to English speaking Maritme Provinces
Can-Fr = French speaking Canada - usually means Quebec but can refer to French speaking Maritime Provinces