I believe this is due to a fight between Edison and Tesla on how best to transport electricity. Tesla wanted electricity to be transported via cables as DC. Edison argued for AC. Edison won here in the stats but I'm not sure quite how that evolved into a difference in voltages.
I don't remember the arguments in favor of DC but the arguments against are obvious - the lines carry higher current which translates to higher losses (hotter lines, less energy making it to your house) and a greater ability to kill you very quickly.
The advantages of AC is mainly efficiency in that you use High Voltage lines meaning copper cables with a smaller diameter (less material) and less loss over distance than DC.
Tesla was brilliant but transporting electricity as DC is a bad idea.
I am assuming that since Tesla was European and Edison was American that the fight over DC vs. AC also spilled over into the 110 vs. 240 V outcome but that's just a guess.