Go has been designed to simplify the complexities inherent in concurrent programming. When C was created, it was rare to have multiple CPUs in a single machine, let alone having multiple cores per CPU. Today, both are the norm, and with the end of Moore's Law, the number of cores will only continue to increase.
There is often a confusion about concurrency and parallelism, so we'll quickly define the two. Concurrency is a way to structure a program by breaking it into pieces that can be executed independently. Parallelism is about running those pieces simultaneously. Concurrency is about structure; parallelism is about execution. Often, a concurrent problem solution can be parallelised, but we'll focus on concurrency.