Character is fate Does The Mayor of Casterbridge show this to be truth?

It can be argued both ways... Henchard does make a lot of his own decisions. This shows free will. The wife sale is an example. However, coincidence and fate also plays a large role in the story. For example the re-appearances of Susan, The Furmity Woman (in the court), and Elizabeth's father all pile up to destroy Henchard's reputation.