Last time I checked the map Judah and Israel were united as one nation upon the mountains of Israel. I think the nation is called Israel.
But then I could be wrong about that too.
They won't be united until - and one king shall be king to them all; and they shall be no more two nations, neither shall they be divided into two kingdoms any more at all: That hasn't happened yet.
The "Nation" of Israel is not the same as the "House" of Israel. The 10 tribes (considered the lost tribes) were of the north. I don't know the year of the map you pictured but all the tribes were there at one time. Also remember, that today many that don't understand the separation, improperly consider Israel as Jews.
My point being; is this a current map of Israel, the nation of Israel or is it one of long ago when all tribes were there? Even the name on your map separates them by saying - The kingdoms of Israel and Judah. There is a difference.