Through systematic analysis of North Sea peat layers — termed Earth's geological archives — scientists decoded the mechanisms behind drastic sea-level fluctuations over 10 000 years ago. Utilizing an integrated methodology combining radiocarbon dating, X-ray fluorescence (XRF) core scanning, and diatom fossil analysis, the study reveals continental ice sheets as dominant drivers: The Laurentide ice sheet (covering Canada) contributed over 20 meters to sea-level rise through meltwater discharge, while Antarctic ice sheet unexpectedly added 8 meters, demonstrating their underestimated vulnerability. During peak melting phases around 10 300 BP, sea levels surged at 9 mm per year — triple the current rate. A catastrophic drainage of North America's glacial lake Agassiz 8 300 years ago released freshwater equivalent to a 0.5-meter global sea-level rise within 34 days, triggering a 200-year climatic cooling event. Concurrently, post-glacial isostatic rebound caused Scandinavia's crust to uplift at 9 mm per year. The ecological collapse of Doggerland's wetland ecosystems and subsequent human migrations, evidenced by submerged archaeological remains, provide a crucial analogue for predicting the fate of modern deltaic regions facing accelerated sea-level rise.