Where do minions come from?
They just poof into existence... where do they come from? And where are they going?
They just poof into existence... where do they come from? And where are they going?
When a mommy minion and a daddy minion love each other VERY much...
I'm sure that there is a lore story behind it-
Oh wait
That is a good question. WE NEED MINION SPAWN ANIMATIONS. We got jungle monster spawn animations.
I thought they were summoned and controlled by Newbie summon--
Oh shit that's right. Um. They appear from... Our tears?
I don't know, man, but it keeps me up at night...
where are we going? 
Before the BS Retcon, minions were supposedly created by Nexus magic. There were rumours that the minions were sentient, manufactured from corpses. I would even take it a step further and say that the minions were former criminals who were executed by Fiddlesticks, the League's executioner.
I'll just leave this here:
They are constructs created by Summoner's (Now super spooky wizards that are fucking powerful and dangerous and want to help people) to help solve conflicts (There must be a shit ton of conflicts on Runeterra) and their bodies are animated using magic. I assume that when the match is over the magic leaves the minions and they are stored somewhere, and that when a minion dies the remaining parts are taken to the nexus to magically regenerate until they're needed again.

COTTON EYE JOEING!!!
https://www.youtube.com/watch?v=V3mZVLqcIYE and here's your answer
Let's just say they appeared from the nexus when summonses rift was built easy as that ......
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