just heard this story and did some digging
and this is the reason why the Brits and some other countries rive on the "wrong side"
what was said in response was pretty close,
but the pope said do it that way. So, when the English became protestant why didn’t it change in protest
and French nobility are some (rude words here)
http://www.amphicars.com/acleft.htm
The US drives on the right because Ford was the first to mass produce cars in the US. Henry Ford’s design had them on the left and since Ford controlled the market, the law was written to the design and not the other way around as it is now.