When and why did "footballs" take their distinctive oval and round shapes? RE, England
In the early 19th century, the game of football played in the major English public schools took many forms. The versions played at Eton, Harrow, Winchester and Rugby all had their idiosyncrasies.
Footballs, though of differing size, were roughly the same shape, approximating spheres that were slightly flattened at their poles, like Ppanet Earth. This was the natural shape that occurred when a blown pig's bladder was cased in leather.
By the mid-1850s it was common practice for footballs to have an outer casing of four treated leather panels sewn together. Even so, the balls made by James Gilbert for use at Rugby School, though considerably rounder than today's specimens, were considered distinctly oval enough to make them ideal for drop-kicking, which was an important feature of the early form of the game played there.
As mass produced rubber bladders replaced the old pig's bladder, so shaping footballs became a more refined, accurate process. The spherical ball, better for dribbling, became the norm in matches played under soccer rules; the more pointed, oval specimen was ideal for games under Rugby rules.
For all that, it was not until 1892 that the Laws of the rugby game actually laid down that the ball must be oval in shape and prescribed dimensions for length and width, as well as ball weight and even panel stitching - "not less than 8 stitches to the inch."
John Griffiths is a widely respected rugby historian and is the author of several sports books, a regular contributor to the Daily Telegraph and co-author of the IRB International Rugby Yearbook. He has provided insight for Scrum.com since 1999.