Josh takes place in Ryan Creek, a small Australian country town about one hundred miles from Melbourne, during the summer of 1936. All of Josh's cousins on his father's side of the family, even those younger than he, have visited Aunt Clara at Ryan Creek during their summer vacations. Aunt Clara is the oldest of the Plowman clan and the only Plowman remaining in the family home.

The town Ryan Creek was founded in 1853 by Josh's great-grandfather, a member of Parliament, who also designed and built the log railroad bridge across the creek in 1882. This bridge, he hoped, would make Ryan Creek prosper.