What this song renders
Sviatoslav was one of the most successful campaigners of tenth-century Eastern Europe. He destroyed the Khazar Khaganate in 965, opening the steppe to Slavic and Pecheneg expansion. He fought in Bulgaria and held parts of it briefly in the late 960s. He challenged Byzantine power directly and lost, but only after years of pressure.
He also rejected his mother’s Christianity emphatically. The Primary Chronicle records his stated reason — his retainers would mock him — in a passage that reads as the Chronicle’s loving disappointment with him. He was a war-prince in a war-prince’s tradition; the Christian framework Olga had brought from Constantinople was, to him, a liability.
Sviatoslav died in 972, ambushed by Pechenegs at the Dnieper rapids on his way home from the failed Bulgarian campaign. The Pecheneg khan made his skull into a drinking cup. Vladimir, his son, would convert the Rus’ to Christianity in 988 — finishing what Olga had started two generations earlier.
Sviatoslav’s campaigns and his rejection of Christianity are documented in both Rus’ and Byzantine sources. The mother-son tension the song renders is in the Chronicle, though softer there than in the album’s reading.