One of the first sodas ever to be created would be Moxie. I was reading random trivia articles as I enjoy doing and was fascinated by Moxie. Created way back in 1876 it is the OG carbonated soda, existing just before other famous brands like Coca-Cola. Unlike other old-timey drinks, it didn't have booze or cocaine at first either. It's mostly been the same for quite some time. A bit like root beer, I read it contains gentian root extract and therefore is sweet but has some bitterness to it. When first created it was advertised as being medicinal, but over time became more of a recreational soda. Coca-Cola actually bought the rights to it in the earlier 2000s and owns Moxie now. It is still pretty popular in the Northeast and is the official soft drink of Maine, but otherwise is a bit hard to find unless you order it online. I wanted to try the first-ever soda, so I got some off Amazon. I liked it.
Moxie is an acquired taste. It is an old soda but strangely enough, reminds me of some of the newer organic and herbal sodas due to its gentian root. I'd say this is more like root beer than a cola without a doubt and definitely has a little bite when you sip on it. I was pleased with Moxie but would completely understand if someone else did not like it. That said, it is fun to take a bit of a trip to the past by sampling the original carbonated soda all these years later.