By the end of November all the churches in Paris had been rededicated to Reason.

Which makes today Quintidi, 15 Vendemiaire CCXVII (217) per the revolutionary calendar.  Rather than associate the days with Roman Catholic saints, the days were associated with plants and animals and other things that weren't saints.  Today's day is associated with donkeys.

#3 Even to a good proddy like me that's a bit difficult.

 

I speak adequate French but that's too idiomatic for me. What's that mean MBP?

vendemiaire is grape harvest

 

5 Brumaire (Quintidi) = 26 October 6 Brumaire (Sextidi) = 27 October

 

Cribbed from Google