Question: I was rewatching Stargate-SG1 and noticed something while I was watching "[Menace](http://stargate.wikia.com/wiki/Menace)" where we learn that the android Reese created the Replicators and sent them out in to the galaxy.

We know that the Replicators integrate technology they consume to their own and lastly we know of no race that were capable of travelling between galaxies (and that lives in the Milky Way) aside from the ancients

My question is, how did they end up in the [Asgard galaxy](http://stargate.wikia.com/wiki/Ida) (Ida) and why didn't they consume everything in the Milky Way long before the series began?

Is is ever explained?

![enter image description here](https://i.stack.imgur.com/jJP0K.jpg)

Answer: 
The short answer is that it's not explained in canon. Although the Asgard have had a presence in the Milky Way Galaxy for a very long time (and hence it would be logical to assume they encountered the Replicators there) Thor [explictly states](http://stargate-sg1-solutions.com/wiki/3.22_%22Nemesis_Part_1%22_Transcript#Transcript) that they were first encountered in the Ida Galaxy.

> 
> **THOR :** ***They were discovered on an isolated planet in our home galaxy*** some years ago. The creators were not present.
> 
> 
> **TEAL'C :** *Most likely destroyed by their own creation.*
> 
> 
> **THOR :** *The Replicators were brought aboard an Asgard ship for study before the danger could be fully comprehended.*
> 
> 
> **O'NEILL :** *We do that all the time. I kinda expected more from you guys.*
> 
> 
> **THOR :** *Overconfidence in our technologies has been our undoing. The entities learned from the very means that were employed to stop
>  them. They have become a plague on our galaxy that is annihilating
>  everything in its path.*
> 
> 
>
reese's planet was an ancient outpost for a small civilisation living in Ida, thus explaining the lack of other ancient tech. The people tried to evacuate home to The Ida Galaxy, but the replicators followed them and killed them anyway consuming all the ancient tech they could, the ancients tried to destroy what they can and so all the replicators went through in order to get as much as they could. This gives them a head start on the Asgard making it harder for them to contain/beat them. The ancients destroy the stargaze to late, allowing all the bugs through but essentially trapping them in Ida. Fan explanation, but not contradicted anywhere to my knowledge.