For me it was in the Spring and summer of 2003.
In Spring I was, as often, seeking the Holy Grail of fantasy strategy games, as for some years before since MoM... I stumbled - don't remember where - on some web resource directing me to the deep buried IW site
. It was Dom:PPP time still ! But as I read the game description I was mislead by all the religious references and thought it was some sort of "god game".. Quit without trying it !
Instead I bought AoW2... Played it some, then, in july or so, get bored by the lack of "epicness" of it. But I roamed the AoW2 forums, and some guy (can't remember who..) started a thread on other games, and talked about Dominions. The thread growed and other posted infos and bits about the game.
Now it looked better, I went back to IW and tried the demo.. I think I was hooked nearly instantly, the game smelled of untold deepness
.
I played solo for a time, then quickly roamed csipg ng, contacted the smallish French speaking Dom community of the time (namely Fa, Nagot Gik Fel, Pocus and Sunray), and had my first MP game, still with the demo !
It acted as some permanent binding spell - I was crushed in this first MP but still remember the first big battles between my proud army of Arco hoplites and elephants and a much smaller Vanheim army... that had much more mages, my hoplites were decimated by Van lightning, my Elephants wounded by Dwarves'Wind Blades, then they routed and trampled my survivors ... ugly !
At that time I realized how deep and rich it was, and I voluntarily bought Dom:PPP just a couple months before Dom2 was released just to "help" IW
.
Needless to say I wanted to get my hands on Dom2 as soon as possible ! I get it and immediately played it MP.
Since then I've always played Dom2, with 1 to 6 simultaneous Pbems going, never got bored.
Still enthralled and waiting for Dom3 !