Another first Saturday in May is here, and the eyes of America turn yet again to Louisville. The Kentucky Derby is as much spring rite as sporting event. Once more mint juleps will flow, ladies will wear hats so outrageous they can only be seen in public this one day of the year, and tears will slide down countless cheeks as the sad lyrics of “My Old Kentucky Home” drift across Churchill Downs.

The race has been run without interruption since 1875. But once it not only missed May, it came within a whisker of not being run at all. This is the story of the year there almost wasn’t a Kentucky Derby.

January 1945: As the new year began, American troops in Europe were recovering from the bloody Battle of the Bulge. In the Pacific, the Navy and Marine Corps were making final preparations for the upcoming (and equally bloody) Battle of Iwo Jima. In Washington, a man named Jimmy Byrnes had a sticky problem on his hands.

The former congressman, senator, and Supreme Court justice was serving as director of the Office of War Mobilization. It coordinated all government agencies involved in the war effort. Byrnes’ power was so immense he was nicknamed the “assistant president.” If Brynes decreed it, it happened.

While the war was going in the Allies’ favor, its outcome wasn’t a certainty. Byrnes’ job was to keep the American military machine fully equipped and to remove anything hampering that effort — which is where horse racing enters the picture.

Believe it or not, the “sport of kings” was affecting the war effort. Moving all those thoroughbreds from one race track to another burned gasoline and tire rubber that were desperately needed on the front lines. Hundreds of millions of dollars wagered on races was money that could be spent to buy war bonds. All those able-bodied workers who kept the tracks open and the horse farms operating could be serving in the armed forces.

But banning horse racing for the duration of the war wasn’t easy. First, it was far more popular back then than it is today. Fans would be furious. (Track attendance jumped during the conflict by 2 million; betting nearly doubled from 1943 to 1944 alone, with $1.2 billion wagered.) No other sport was canceled because of the war; why should horse racing be the only one to suffer? The Senate’s powerful majority leader happened to be Kentuckian Alben Barkley, who had a vested interest in making sure the ponies kept running.

Byrnes had come close to banning horse racing in early 1943. Racing interests had prevailed then. But their luck eventually ran out. Byrnes announced a total ban on all horse racing on Jan. 3, 1945.

This meant no Kentucky Derby for the first time since the tradition had started in 1875. Horse racing fans in general, and Kentuckians in particular, were crushed.

Then fate intervened.

Nazi Germany surrendered on May 8, ending the war in Europe. Byrnes quickly lifted the ban on America’s beloved sport. Organizers had to scramble to put it together, but there would be a 1945 Kentucky Derby after all!

Sixty-five thousand fans filled Churchill Downs on a rainy Saturday, June 9, for the 71st edition of the "Run for the Roses." They watched legendary jockey Eddie Arcaro lead Hoop, Jr. down a sloppy track to victory by six lengths. His winning time of 2:07 was solid, if not impressive. There was no Triple Crown winner in 1945, though Assault would become the seventh horse to claim the prestigious honor the following year.

It was also the only time the Kentucky Derby was ever run in June. But horse racing fans (myself included) are a sentimental lot and tend to overlook that sole deviation. All that mattered was the tradition stretching all the way back to the days when Ulysses S. Grant lived in the White House remains unbroken.

J. Mark Powell (@JMarkPowell) is a contributor to the Washington Examiner's Beltway Confidential blog. He is a former broadcast journalist and government communicator. His weekly offbeat look at our forgotten past, "Holy Cow! History," can be read at jmarkpowell.com.