Why do different countries use different mains voltages?

Why do different countries use different mains voltages?

the biggest disparity is between the usA on 110V and most of the rest of the world on 230V. America’s lower voltage goes all the way back to thomas edison, who introduced direct current (dC) mains electricity at 110V. edison’s rival nikola tesla showed that long power lines transmitted alternating current (AC) more efficiently than dC. His AC approach won out, but he stuck with edison’s 110V. But by the time electrification spread to europe early in the 20th Century, lamps had filaments that could give out more light and handle greater power loads. so the Berliner elektrizitätswerke company in Germany established 230V as the standard.