Sorry Serge, I beg to differ. Yes, the Europa name was used right from the beginning. Well not quite, they had a few names kicking around at first. One of which was the "Concorde". No rear badging though until the S2: no L-O-T-U-S letters, no Europa/Europe badge. The only thing at the back was that the very early cars had "Odi" fasteners -- a good idea that shouldn't have been dropped. Perhaps a few people added emblems after getting tired of being asked what the heck their car was. It's also not uncommon to find S2 doors and windows put on as they are a lot more functional than what any S1 had.
So find me a period photo with the emblem in place and I will believe (hallelujah), but not until then.