Actually, Monsieur Banto, you were on the right track. A quick-witted and amorous member of the French aristocracy, the Marquis de Chatouiller indeed invented the balloon in 1726 whilst dallying with a young chambermaid in an upstairs bedchamber in his palace in Brest of all places. Being conscientious and trying to avoid yet another paternity scandal he had the good sense to be using a sheepskin prophylactic when his suspicious wife Giselle came home. Having been caught out with these ‘devices’ before, and in no way desiring yet again to be the recipient of the all too familiar fury of scorn about to be unleashed, he withdrew it, blew into it till near bursting, tied it off with a trailing piece of string and let it go in the breeze blowing by his balcony door. This French tickler was no laughing matter.
As for the color Monsieur Banto; well rumor had it that when the peasants in the nearby fields beheld this "premiere balloon" floating above them it was reported by them to be nearly translucent, with only a few flecks of red. L’amour, toujours l’amour Monsieur Banto.

Any serious discussion of the origins of the balloon really necessitates a discussion of word’s linguistic origin. As you may or may not know, the word ‘balloon’ was imported into the English language from the Old German version of the word, which is ‘bayoon’. A ‘bayoon’ in medieval times was a breathing device that peasants and villagers would use to retrieve items from deep water lakes, lagoons, and rivers. Many of the early ‘bayoons’ were, as pointed out earlier, made from pig bladders. Like any technology, it improved, and eventually ‘bayoons’ came to be made out of fabric called zerwitz, which is plant product similar to cotton but with distinct properties that make it useful for constructing ballons.

So where does the Old German version of the word come from? ‘Bayoon’ was brought to Old German from the ancient Babylonian word ‘baehoorus’, which is a word that translates into ‘object with which sky and sky are separated’. It seems that the ‘baehoorus’ was originally a chamber within ancient blast furnaces that was used to recycle hot air back into the furnace. Anyways, I’ll spare you the more detailed explanation.

If you think about the color of these first, protean ‘balloons’ as they existed in ancient Babylonia, then it is very likely that these original ‘baehoorus’ were black, largely as a result of soot from the ancient furnaces.

Hope this helps to answer your question!