When did ballet begins and where?

The first forms of ballet started during the Renaissance period. King Louis of France first 'invented' ballet to entertain him. It was performed to him by his court members.
The first official organised ballet was, again, performed for King Louis, in France. It lasted an impressive 42 hours! The dancers would have wore difficult and extravagant costumes, which would have been very heavy and elaborate, making it really hard to dance in, especially for that long!

So, um, er, yeah....
Hope this helped :)

Principal Dancer At The Royal Ballet