Ask HN: What's the untold story behind Notion?

You’ve probably heard the popular version of Notion’s story—how the team faced struggles, went to Japan, and eventually built the product we all know today. But I’m curious about what happened before that.

According to Wikipedia, Notion was founded in 2013 by five people: Ivan Zhao, Chris Prucha, Jessica Lam, Simon Last, and Toby Schachman. I've also heard rumors that it was the result of a merger between two startups.

Has anyone come across a detailed account of this early history? Would love to dig deeper into how it all started.

Thanks in advance—this community is always the best at uncovering these kinds of stories!