The Year of the Three Emperors, the…
1888 CE
The Year of the Three Emperors, the dying Frederick III inherits the German imperial throne from his father William I on March 9, 1888; his son succeeds him as William II on June 15.
The mnemonic “drei Achten, drei Kaiser” (English: "three eights, three emperors") is still used today in Germany by children and adults alike to learn the year in question.