heywood,
You have convinced me with one tiny piece of information! First, I should explain that my expertise is in researching buildings not people - although I try to confirm the identities of people who lived or worked in those buildings.
With no disrespect to you or others who have tried to help me, I was sticking to the information as given in the 1871 Census. Clearly I was wrong to do that.
I had no hesitation in accepting that he would come to Flint Hill from Hexham as many agricultural workers did - mostly to find better paid work in the coal mines. My problem was in understanding the Chester-le-Street/Hett Hills connection. Although this area is only 8-10 miles away, there is no direct connection.
The building was given in the 1871 Census as Four Lane Ends public house, Flint Hill. There has never been a pub of that name but what is now known as Flint Hill Bank is shown on old OS maps as Four Lane Ends and there were two pubs on that road. I am trying to identify which he managed. I cannot check the brewery records as both breweries have long gone. The one vital clue you gave me showed that his daughter Margret Hart was born in Flint Hill which was a thriving though very small village in 1871 but had no direct connection with the Chester-le-Street area. However, his in-laws were publicans so that might be the connection. His time here appears to be limited to 1871 so it seems he failed as a publican and went back to being an agricultural labourer.
If I can prove he was the son of the Isaac Hart who was transported to Van Diemen's Land (Tasmania) -as it seems he was because he was brought up in Hexham Workhouse - that would add interest to the story.