system
Given the following post, respond as if you're commenting on Reddit:
human
[Doctor Who] Torchwood was set up in 1879 yet there isn't a single mention of it in 26 years of Classic Who, why didn't they help out with any of those invasions?
gpt
Well, with these types of questions it's always helpful to remember that the first rule of Doctor Who Cannon is that there is no Doctor Who Cannon, and that anyone who says otherwise is trying to sell you something.

But in reality, presuming they weren't a retroactive result of the Time War, one of the original aims of the Torchwood Institute, as set out by Queen Victoria, was to capture the Doctor. As such, it makes sense that for their first twenty years, Torchwood would do their best to remain a secret and not attract the attention of the Doctor. 

As soon as Jack was recruited in 1899, that all would have changed, as he would have obviously pointed out the obvious logical paradox in capturing the Doctor before he even finds out Torchwood exists, let alone creates it.