The popularity of Touhou series didn't reach the Western world for a few more years. The tipping point in Japan is thought to be the 8th title (Imperishable Nig

The popularity of Touhou series didn't reach the Western world for a few more years. The tipping point in Japan is thought to be the 8th title (Imperishable Night in 2004) and I believe it took another 3 or 4 years for Touhou to be reasonably popular outside of Japan; the earliest known "Touhou hijack" in 4chan was around 2008 for example, and as a South Korean, I myself learned of Touhou in c. 2006 via a doujin music. The 6th title then became popular among other titles in the series somehow.