The fiddler's Kunta's first real friend in America. Although this outgoing, life-of-the-party musician doesn't have much in common with the uber-serious Kunta, they provide each other a great deal of comfort when they need it the most.
Plus: that fiddle music is a big bonus.
Sadly, the fiddler's own story is pretty tragic. The dude has earned a bunch of money over the years playing local gigs, and confides in Kunta that he's been saving up to buy his freedom for a previously agreed-upon amount from Massa Waller. Sadly, Massa Waller ends up denying the fiddler's request by saying that prices for slaves are going up, leading the fiddler to throw his violin into the river, a symbolic representation of his shattered dream.
Although the guy gets depressed after this, he comes back around when Kunta gets ill because he's that concerned for the health of his best friend. This is yet another reminder of the importance of community and friendship. We might not know exactly how the fiddler's story ends up, but we can take a small amount of comfort knowing that he and Kunta will be Bert-and-Ernie-level bros for life.