Let's not forget node.js wasn't created in a vacuum but was based on CommonJS (module format and std lib) also implemented by TeaJs/v8cgi, Helma, and many others [1]. In fact, server-side JavaScript was a thing as early as 1999 or before (Netscape Server). That it's based on a highly portable language also used on the browser is what made it attractive over alternatives for me back in 2012 or so.

[1]: https://en.wikipedia.org/wiki/List_of_server-side_JavaScript...