They would celebrate the way they still do. Just without certain technology.
In early modern times most people made their money off of agriculture or working in factories
"does 'Mardi gras' mean 'merry times' - 'Fat Tuesday' - or 'Spring Welcome'? (well, fat means 'gras' in French, and Tuesday is spelled 'mardi' ...)
Good Food, Great Times, oh and this little thing called Mardi Gras.
we are more smarter now
In England, they spoke English. Not Old English, not Middle English, but Modern English. There were a number of dialects of Modern English spoken which are lumped together as Early Modern (or Elizabethan) English. It is the same language I am writing in now with a few quirks.
food
You don't mention a timespan. In early modern times (1600-1800) doctors (physicians) were allowed out at any time to visit patients.
Most people lived in Europe and Asia.
Forests.
The Middle Ages hung people for stealing or robbery while in early modern history people were incarcerated. It was felt that rehabilitation was possible for crimes,but the methods used were inhuman. Incarceration often included torture, leaving people in solitary, and having them in cells 24-7. Some went mad over this treatment.
Well there was 453,728 but now there are about 239,124 people in New Orleans science Hurricane Katrina and not all people in New Orleans celebrate Mardi Gras so i"ll say like 162,099 people celebrate it.
After WWII people could no longer become samurai, but the devotion of samurai is still used in modern times.