This idiom means returning to the starting point after an effort fails or progress is undone, often with a sense of frustration or wasted effort. It’s used when plans, projects, or negotiations collapse, requiring a fresh start, and conveys the need to regroup or rethink an approach.

The phrase likely originated in the 1930s from British radio commentary on soccer or board games like Snakes and Ladders, where ‘square one’ was the starting position. A 1939 BBC broadcast referenced ‘back to square one’ in a football context, describing a return to the initial field position. Another theory links it to the board game Ludo, where players return to the first square after a setback. By the mid-20th century, it was common in British and American English, appearing in business and political discourse.