Josiah Alfred Hanan, known to his colleagues as Joe Hanan, was a New Zealand politician, cabinet minister, and legislative councillor. He also served as Mayor of Invercargill, and as Chancellor of the University of New Zealand.

The Mayor of Invercargill is the head of the municipal government of Invercargill, New Zealand, and leads the Invercargill City Council. The mayor is directly elected using a First Past the Post electoral system every three years. The current mayor is Nobby Clark. Invercargill also has a deputy mayor that is chosen from the council. There have been 44 mayors so far.