Press the button and a world map from some moment between 1945 and today appears on the globe.
Spin it, zoom in, read the borders and names — then enter the span of years you think this map was accurate for. If every year you name falls inside the true window, you win.
Borders: CShapes 2.0 (Schvitz et al. 2022), non-commercial. Names are shown as they were at the time.