How did you get on?  This was meant to be challenging but we were a bit disappointed by the number of our  Buonapartistas who rose to the challenge!  We thought you'd enjoy burrowing into your reference libraries and digging and delving on the web, and hope some of you did do just that.  Mike will be contacting prizewinners shortly.

Here goes with the answers....
Image 1

1.1   How old is he?  28. Jacques-Louis David did this sketch in 1797 for a grand painting, which he didn't finish, of the signing of the peace treaty with...

1.2   Who has he recently defeated? ...the Austrians.
Image 2
2.1 What is the month and the year? March 1814.
2.2 Where is he retreating from?  From Laon, where he had failed to repeat his earlier, brilliant success over Blucher at Craonne, and would not have been able to extract his outnumbered army if a small detachment of the Old Guard had not mounted a heroic rearguard defence. The painting is by Jean-Louis-Ernest Meissonier. 
Image 3
3.1 Which battle? Eylau (February 1807)
3.2 What did he want the picture to display? The Emperor wanted the picture to display his compassion as well as his military prowess, and he does look quite saintly as he gives comfort to the wounded and defeated.  The painting was done in 1808 by Antoine-Jean Gros who won the commission in a competition which he reluctantly entered, beating 25 of his contemporaries to the 16,000 francs fee and a prime position on the walls of the prestigious Salon of 1808.
Image 4
4.1 Who is conspicuously leading from the front here? The bravest of the brave, Marshal Ney.
4.2 Where? Kowno in December 1812, on the Russian border with Prussia.  This desperate final rearguard action was well described in 1825 by Count Philip de Segur 
4.3 What (apart from a certain chilliness) specifically connects this picture with one of the others? Ney also features in 2, riding just behind Napoleon.