The phrase “back to square one” or “back at  square one”, which was how it was first said in the 1930’s came from the football radio commentaries of the 1930’s. Due to lack of pictures at that time, these live  reports would explain the position of play by  dividing the football pitch into numbered grids  and “square one” was just in front of the goal. Hence, when a ball went out of play and resulted in a goal kick, the play was “back at square one” which over the years became popularly in everyday life as ‘back to square one’ indicating the return to the starting point.