Pre memes we had movies like Billy Madison and Tommy Boy. Those quotes are permanently part of my vocabulary. “Stop look at me swan”, Housekeeping. You want mint for pillow?".

The oldest actual meme/Internet thing I regularly reference is “here is the earth, round” or "the cheat is grounded "

Does telnet towel.blinkenlights.nl count?

i still reply 14/f/cali anytime asks me my age.

and thats from like…the early/mid 90s. before memes as we knew it were a thing.

Ceiling cat, trogdor, “drop a train on them”

I cannot really remember what is the oldest, but a lot of old Team Fortress 2 gm videos, live rent free in my head, and I quote them (especially just the weird noises) all the time. And I still follow the creators, that make new ones. It has evolved into a full genre over the years.

//Edit
I went and dug through my playlists. This is “only” 10 years old, but I think it summarizes well, both the absurdity of them, and how far from the actual game, the genre is.

Boom Headshot

I cast magic missile at the darkness.

Whenever someone turns to look behind them, I turn them into a pillar of salt.

It’s just this fun thing I do.

Mr T Ate My Balls, a member of the Ate My Balls Webring

kids today don’t know what a webring even is

C-C-C-COMBO BREAKER!!!

https://britneyspears.ac/lasers.htm

These fine owls are still living rent free in my head.

But the worst are probably Goatse, 2girls1cup, 1guy1jar, all the nazi ascii stuff. Modern day memers have it easy.