According to his 1909 death certificate, John lived in Chicago for 45 years. That agrees pretty well with the 1900 census which says he immigrated in 1863.
John's occupation is listed as ``teaming'' in the Chicago City directories for 1903-1905, with an address of 113 Park Av. No occupation is listed for him in 1907 or 1908. His death certificate gives his occupation as a retired team owner.
According to Mary (Shannon) Flood, she was told by family members that the John Shannon who ran a livery on Park street was a brother to Michael. This all checked out and record of John's baptism was found in Ireland.
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I think the photo of Mr. and Mrs. John Shannon was more likely to have been taken around 1875 when they got married, rather than the 1870 date that the photo had captioned on it.
Sources for this individual: @S6@