This song's author is unknown, but it was written around the time of the Jacobite rebellions.  I love the archaic language and sing it to myself when nobody can hear. It has been recorded a few times, notably by Steeleye Span (it's on youtube).
Now the history lesson. In 1688 James II, a Catholic, was exiled to France and his Protestant daughters took the throne, first Mary, then Anne. When Anne died without heir, the throne passed to the house of Hanover.  George I became king, even though he was German and spoke no English. But he was, crucially, Protestant.  
The son of the exiled James II made a claim to the throne but he being a Catholic, was not accepted. His son also tried, Bonny Prince Charlie. These were the Jacobite rebellions.
Come ye o'er frae France is a song in support of the Jacobite movement,  and very much mocking George I.   My rough explanation of the archaic language is as follows.

Have you just arrived from France?
Did you come via London?
Did you see young Georgie and his pretty woman?
Were you at the place they call the ***** house
Did you see George his grace, ******* a ******?

Georgie, he's a man, there's no doubt about that
He has anyone he can, and who wouldn't?
Along came a dish, swanking like a dandy
And he did a deal
To share poor Georgie's candy

Although we got a bad deal, still we blithely haggled
If we get the dregs it makes little difference
We have dyed our cloth, bonnet belt and sword,
Our homes and lands are lost, but we have our George!

The **** (James) has gone to France with Montgomery's lady
There they'll hatch a plot, and when they're good and ready
They'll be back here soon, kitted up and raring to go
And may they succeed in their set-to with Georgie!

Come on Sandy Don, come on Cockolorum   [Jacobite supporters]
Come on Bobbing John and his Highland Possie
Many a sword and lance swings a Highland warrior
How they'll skip and dance over the *** of Georgie!