Which came first? The Doom 2 or the Quake?

I know this may sound dumb to you guys but I find it kind of odd. While I was looking through some old cds, I came across the cds for Doom 2 and Quake. But something was wrong... The rating for Doom 2 had the modern M rating on it, while the Quake cd had the older rating system (The one that showed that thermometer). If Quake had indeed come out before Doom 2, would id software not have utilized this new engine for the Doom 2, rather then the old doom engine? But if Doom 2 had come out before Quake, wouldn't it use the old rating system?

Doom 2 - September 30, 1994
Quake - May 31, 1996

My disk based Doom2 1.666, bought on the day it came out, bears none of these marks.

The talk is about the Stateside release: Here both Doom and Quake were BBFC 15's ;)

Yeah, I thought that might be referring to stateside markings, but I have seen both the marks mentioned on games bought in the UK. On closer inspection of my Doom2 box, I see it has an ELSPA rating panel. The 3-10 age box has a red cross in it, as do the 11-14 and the 15-17 ones. The 18+ box has a green tick.

Must have been before the BBFC got their mitts on it: My Doom II CD had the "15" stamp on it.

yeah my quake has some old rating system on it too

well, if you bought quake before doom2, i could see this happening.