It mostly is. The island was the original IIRC, and as the settlements spread, the name of "That hunk of land actually further north than the island" was a bit too cumbersome to use.
Kinda like names on other locations and even housing developments. We have one residential area that is "College Park" so named apparently since:
1. it isn't a park or near one
2. no college
but aside from that the name is a perfect fit.
Why is there a Northumberland but not a Southumberland? Or even an Umberland. When we gained the Dakotas, we made sure we had a North Dakota and a South Dakota.
You may say "But you have a West Virginia without an East Virginia, to which I'd reply, "OK fine…where's Umberland?"
While I'm asking pointless and inane questions, ever hear of the band "Better than Ezra?"
betterthanezra.com
Have you ever heard Ezra? Shouldn't we get to decide for ourselves?
And why do we give in to those hard line commies in China?
Do you talk about Espania? Sverge? Polska?
No?
Then why don't we call Peking by the name it always had? Just kowtowing to those commie bastards it seems. I don't order Bejing Duck in a restaurant. I don't watch "55 Days in Beijing."
When introducing his famous hit "Sittin On The Dock At The Bay" the DJ's always say it is by "…the late, great Otis Reading." Really? Quick – name three other songs he's done. Heck, name one.
And what's with the Mexican province "Baja California?" Who was Baja anyway? Why isn't it Baja Mexico? Why call it that at all? Know what Baja translates to?
link
Speaking of "south of the border, why is "Jorge" pronounced "Hor-hay?" Something against the letter "H"? Even without that why isn't it Jorje or Gorge if both J and G are H?
And why aren't copiers pronounced "Zeroz" or "Ecks-rocks" as X is the reverse situation – the same letter being used for two totally different sounds rather than two totally different letters being used for the same sound?
Ponderous, man…ponderous.