Yes, yes, it’s true. Britain’s right, (or should that be left?) and the rest of Europe ( pre-Brexit!) is wrong!
In the middle ages, the roads were dangerous and travellers automatically kept to the left, to oblige strangers to pass them on the right. Assuming that right handers are in the majority, this meant that they could go for their swords more easily if the stranger was a baddy! Maybe a little unfortunate for left handers in a fight but majority rules!
Travelling on the left was actually made official in 1300 AD, when Pope Boniface VIII decreed that pilgrims to Rome should keep left.
It wasn’t until the late 1700s, when goods wagons pulled by teams of horses, had no driver’s seat, that this was to change. The driver would sit on the left rear horse, (so he could whip the horses on with his right arm), and therefore drove on the right in order to see and avoid the wheels of oncoming vehicles.
Later Napoleon enforced the keep-right rule in all countries occupied by his armies and today, only four European countries still drive on the left: the United Kingdom, Ireland, Cyprus and Malta.