Thanks to everyone who helped with this. I think I've found out just about everything I can with the Fields and am amazed at how much I was able to get with your assistance. Thanks so much!
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Can someone help me wrap my head around what Durham County was around the time of the 1861 Census?
I'm attempting to find my GGgrandmother, Harriet (Field) Bullen. She might have been in the Bowmanville area during that census. Her husband, Jonathan Bullen, had gone to Victoria, B.C. (1860) and she followed him with their 2 daughters, Eliza Jane and Sarah, a few years later. She was born Harriet Field in 1831 to Jeremiah Field and Harriet Howlett, London, England (christened 1833 at St. James, Clerkenwell, London, England) Harriet Howlett was Jeremiah's second wife, the first being Hannah Westley.
I've never found record of Harriet (Field) Bullen or her 2 daughters in Ontario, in spite of the fact I know they were there - somewhere in the Bowmanville area.
I think I've finally located her father in the 1861 census in Darlington Township as a farmer. His wife (Eliza) is not Harriet's mother but I think it's him because in the 1871 census there are Howletts living with him and it seems like too much of a coincidence.
I've paged through the Darlington Township 1861 census pages without success, but what I don't know is - what does this township encompass?
A family Bible shows Harriet Field, Darlington, 10 April 1849 as the possessor, so obviously the family emigrated prior to the 1851 census, although I've never found any sign of them. There should have at least been Jeremiah (b. 1799), Harriet (b. 1831) and Eliza (b. 1833). Eliza married William Doidge in 1860 (Oshawa)
The other thing I'm trying to understand is, did Jeremiah move around or did place names just change? 1861 - Darlington Township. 1871 Pickering. 1881 York.
I live in British Columbia (near where Jonathan Bullen and Harriet Field settled) so am not that familiar with the area.
Big thanks to whoever can help.