“It didn’t help that the North Star starts to shift its position in the sky the further West you go, and Longitude calculations didn’t exist yet”
Hipparchus discovered the precession of the equinoxes and had accurately calculated both latitude and longitude as a grid on our spherical globe in around 130 BC. The problem for a long time after this discovery was the absence of an accurate universal time keeping system to measure longitude. :)
Torsional pendulum was added as the regulation component for a clock to allow time keeping on a ship. British Navy secret for a bit.