The Great Gunpowder-Exodus Timeline Controversy

The one real question I have asked on this blog of all twelve of you, whether you are a contributor to the blog or not, is the two part question of - How late in time are we going to continue the Exodus of Celts from Earth to Garnia World, because they are the only ones on earth that figured out how to operate the portals on their own; and does gunpowder work on Garnia World?

This is mainly a concern for me regarding certain areas of the world that are going to be heavily Gaelic, populated by peoples from Ireland and Scotland and the Isle of Man. Their cultures become heavily Christianized fairly early on, but gunpowder comes to Europe in the middle ages. Scotland had a medieval King, James II at the siege of Roxburgh, killed by an exploding cannon; actually it probably served him right for breaking the tradition of being crowned at Scone. Granted he was an early 15th century King, but gunpowder had been used in European sieges for a couple centuries by then.

I guess part of me wants to save Highland Clansmen from their brutal fates after Culloden, and maybe some old parish priest has an ancient book explaining the ritual to activate the portal and some of the Highlanders can get away; or it could be a Clan chief's bard, or an old wise-woman. It doesn't matter who does it, but that's post 1746.

Now, I understand that this is all dependent on HOW MUCH MAGIC is left on Earth. Like Oil or Uranium, it's a finite resource on Earth and we've pretty much used it all up in the past, which is why miraculous things rarely happen anymore. But given my druthers, I'd also like to save a bunch of Gaelic speaking Irishmen from the Potato Famine, more than a million deaths and most of them the poor Gaelic speakers. I'd like to save a few of them if I could but that's 1845-52, post-Napoleonic wars, making the gunpowder question even more of an issue.

I guess if we save some Highlanders after the '45 they could look like this if gunpowder doesn't work.

But I'd like a reasonable explanation as to why gunpowder doesn't work, because otherwise the guys from after the '45 should also look like this-

Really all of these guys are from Wargames Foundry's English Civil War line, which really makes them mid-17th century rather than mid-18th century, but not a lot had changed in the Highlands in the interim, except, of course for the worsening of conditions under Hanoverian rule.

I haven't found any miniatures for the 1848 Irish rebellion, so I can't show you what they should look like.