Lincoln United Football Club began life as Lincoln Amateurs in 1938, just one year before the outbreak of World War Two, and were admitted to the Lincoln League.

By 1951 the club was in a more stable position financially, so much so, that they were able to sign Ray Bean from Football League side Nottingham Forest, offering him a wage of five shillings which was equivalent to twenty-five pence a week.

However, this action meant that Lincoln Amateurs were no longer amateurs so a name change was required. The obvious choice of Lincoln City had already been taken in 1882 so on a trip to play Sleaford the player's swapped ideas. It became a straight choice between Lincoln United or Lincoln Rangers; the vote went to Lincoln United.

Lincoln United were also readmitted to the Lincolnshire League as they could now afford to travel further a field to their away games. It was in the Lincolnshire League that they won their first honours of the Lincolnshire League Championship and Lincolnshire Senior "B" Cup in the 1963/4 season; effectively this was a league and cup double. Three years later, United had out grown the Lincolnshire League so they withdrew to join the Yorkshire League where better opposition awaited them. Once again United completed a league and cup double, this time in Yorkshire during the 1970/71 season.

A variety of leagues followed including being among the founder members of both the Northern Counties East League and the Central Midlands League.