How UK Would Look Without Scotland, and What 'British Empire' Looked Like in 1901

— -- If Scots vote for independence from the United Kingdom Thursday, the monarchy would lose not only the land of Scotch but about 5.3 million Scottish people, or 8.3 percent of U.K.'s 64.1 million population.

Scotland Vote Raises Specter of Ununited Kingdom

Here's what the U.K. would look like without Scotland: England (53.9 million), Wales (3.1 million) and Northern Ireland (1.8 million).

Below is a map from 1901 showing the “British Empire” at one of its peak periods. The map doesn't convey the extent of British influence, especially, in Latin America. This is what historians used to call "informal empire," according to New York University history professor Andrew Sartori.

The 1901 map includes self-governing colonies, such as Australia and Canada, which were part of the British Empire in both Britain's and their own understanding, Sartori said.