World War III

What happened? There's only one stone, no date.
Only a few fortunate ones were buried at all. It happened so fast, families were buried together. Dates became unimportant as all systems broke down. Finally, there were no more armies or fighting. Only starvation, contamination and lingering death.

 — William "Buck" Rogers and Dr. Theopolis after Rogers comes across a surviving gravestone for his parents, Buck Rogers in the 25th Century's "Awakening"

World War III is a pivotal point in Earth's history.

Occurring later in 1987, Rogers escapes a calamity that befell his plant and time (BR25: "Awakening").