According to this bio/business history, John Connolly was in Minnesota by 1865. Since he would have been in his early twenties at the time, if this story is correct, it is doubtful that he had his own businesses in Newark, NY, and Baltimore, although he may have lived and worked in those places. https://www.vintagegunleather.com/company-marks/connolly_history.html
Another story about his business http://anyflip.com/zbfz/mspf/basic
thanks so much for your help. I am finding our more each day.
Dear Mr. Feehan,
Thank you for posting your request on History Hub!
Most cities and counties have yearly directories for residents and businesses. Some of these directories are indexed by address but most are alphabetical. We suggest you consult the FamilySearch wiki on United States Directories for these resources..
We hope this is helpful. Best of luck with your family research!
Thank you so much!
Welcome to History Hub.
Found Mr. Connolly in the1910 Census in Flathead Montana as a widower on
familysearch.org...family search is a free web site...you just need to register
Found your great-grandfather's obituary on newspapers.com.
The date of death is wrong in this obit..the newspaper date is March 25, 1928