Git was created by Linus Torvalds, the creator of the Linux kernel, in April 2005. With his dry wit, he has affectionately called the tool the information manager from hell. In an interview with the Linux Foundation, Linus mentioned that he felt source-control management was just about the least interesting thing in the computing world (https://www.linuxfoundation.org/blog/10-years-of-git-an-interview-with-git-creator-linus-torvalds/). Nevertheless, he created the tool after a disagreement between the Linux kernel developer community and BitKeeper, the proprietary system they were using at the time. 

The project came together really quickly. About ten days after its creation (yeah, you read that right), Linus felt the basic ideas for Git were right and started to commit the first Linux kernel code with Git. The rest, as they say, is history. More than ten years after its creation, it is still meeting all the expectations of the Linux kernel project. It took over as the version-control system for many other open source projects despite the inherent inertia in switching source-control systems. After many years of hosting the Python code from Mercurial at https://hg.python.org/, the project was switched to Git on GitHub in February of 2017.