For as long as people have been planting and gathering food, I suspect there has been some form of Harvest Festival or, at the very least, a really great dinner when the harvest was done. Here are some pages showing the various Harvest Festivals celebrated in different times in history and/or in different parts of the world.
Australia has a variety of harvest celebrations-
the Lavender Festival the Hops Festival the Apple Festival
the Grape Festival
the Renmark Orange Week Festival the Cane Festival and
the Wheat Festival visit this page to learn a bit about each of them
"Hip!Hip! Hip! For the harvest home,
Now we've taken the last load home
I ripped my shirt and I teared my skin
To get my master's harvest in" (Warwickshire Harvest Song)
The form of wheat weaving known as a "corn dolly" figures prominently in British celebrations, including the well known folk song John Barleycorn.
You might also want to try making a simple corn husk doll.
Finally a page of recipes from harvest festivals around the world Click Here for links to this whole list of great food!
Sweet Candied Potatoes from America
Succotash from America
La Tourtiere from Canada
Moon Cakes From China
Sauerkraut from Czech Republic
Kolache from Czech Republic
Pongal from South India
Poteen from Ireland
Songp'yon from Korea
Courguettes Stuffed from Israel
Pumpkin Bread from America
Apple Cider Punch from America
Sweet Potato Bake from America
Roast Turkey from America
Wild Rice Stuffing from America
Pecan Pie from America
Cranberry Jelly Candy from America
Cranberry Sauce from America