The first record of the name "Belograd" appeared on April, 16th, 878, in a Papal missive to Bulgarian ruler Boris I. This name would appear in several variants: "Alba Bulgarica" in Latin, "Griechisch Weissenburg" in High German, "Nándorfehérvár" in Hungarian, and "Castelbianco" in Venetian, among other names, all variations of 'white fortress'. For about four centuries, the city would become a battleground between the Byzantine Empire, the medieval Kingdom of Hungary, and the Bulgarian Empire. Basil II (976–1025) installed a garrison in Belgrade. The city hosted the armies of the First and the Second Crusade, but, while passing through during the Third Crusade, Frederick Barbarossa and his 190,000 crusaders saw Belgrade in ruins.