> For six months of the year, from February 1 to 31 July, it's under Spanish rule - and for the following six months it's French

If I'm counting right, France has it 184 days per year (185 in leap years), and Spain has it 181 days.

I wonder why they didn't balance that better? April 1 to Sept 30 for France and Aug 1 to March 31 for Spain would have given 183 for France and 182 for Spain (183 in leap years).

The same balance would also arise from June 1 to November 30 for France and December 1 to May 31 for Spain.