Ebul, Glubb had a theory that empires last about 250 years, which he reckons as ten generations. I give some examples below (if it formats correctly).

[pre]
The nation      Dates of rise and fall     Duration in years
Assyria         859-612 B.C.            247
Persia          538-330 B.C.            208
Greece          331-100 B.C.            231
Roman Republic  260-27 B.C.             233
Roman Empire    27 B.C.-A.D. 180        207
Arab Empire     A.D. 634-880            246
Mameluke Empire 1250-1517               267
Ottoman Empire  1320-1570               250
Spain           1500-1750               250
Romanov Russia  1682-1916               234
Britain         1700-1950               250
[/pre]


Note that he sees the Roman "Empire" as coming in two phases, the Republic followed by the Empire itself.

As for the Huns, Glubb remarked that the Hunnic coalition was only a power in Western Europe from 450 to 453 when it promptly fell apart on the death of Attila and the Huns returned to Eastern Europe.

Well I suspect it is easier to create Empires than keep them together, so I would not argue with that Mobo.

Theresa May want's Sharia Law, well there is a women for you?

Still I think she is better than Cameron, which did not say a lot for him.