This huge canvas (the original is 12 feet long by 4 feet high) was a time-consuming labor of love for Simon. He was inspired by several things: he wanted to somehow preserve a vanished phenomenon. in the early 1800's the buffalo population was estimated at about 60 million and 70 years later hunting reduced it to about 200. He had observed wildebeest migrations in Africa so he was fascinated by the movement of vast herds of huge animals. He read the diaries of Meriwether Lewis of the Lewis and Clark expedition and Lewis’ observations of these migrations: he then followed part of their route so that he could find the right spot to place his buffalo herd.

He said: “About 30 miles south of Bismarck, North Dakota, I found what I wanted. It was fall, the grass was golden brown and the trees were autumnal but I read that the Indians would burn the prairies every year to bring new grass and attract the buffalo. Therefore, I had to eliminate most of the trees from the landscape. All signs of man’s hand had to go: powerlines, roads, harvester marks on the grasslands even the level of the river had to be lowered because it was dammed up... a small half-hill had to be restored to its original conical shape; the other half had been used as a highway.”