Which group of people do you think started using abbreviations like bc and ad? why do you think this?

Christians mostly because it refers to their God. B.C. stands for before Christ and A.D stands for Anno Domini which is Latin and translates to in the year of our lord. When they say B.C. they mea before he was born and A.D. refers to after. Right now, it would be considered A.D. 2018

On april 20, 1814, the dethroned emperor left france for the isle of  elba, where he was exiled under the terms of the treaty of fontainebleau.napoleon  would be allowed to ruleelba, which had 12,000 inhabitants. perhaps cruelly, the treaty allowed him to retain the title "emperor."