An alternate history where Norway and England merge.
Harald Hardrada of Norway succeeds in taking over England in 1066. When William the Conqueror arrives with his invasion he is stopped by an army built of Vikings and English who come to the aid of their new rulers, hoping that then they would be more merciful. Hardrada, grateful for help appoints those who helped him as rulers of England. They organize themselves into houses, united yet separate governing bodies.
The tension between the houses of England are high a decade after their creation. Noble king Hardrada sees war on another empire as a way to bring them together. He announces a crusade to please the gods and brings a vast army from England to meet his Norwegians. In 1078 they march East from Norway and on a long campaign claim much land, they meet little opposition and assimilate many into their army until they reach far into Sweden and Denmark. The assimilated army is too great and the Swedish surrender after a few skirmishes. The only major battle in the war is on a extensive field, where Briton archers tear apart enemy formations and Beserkers storm into the fray. The campaign stretches right into Russia before grinding to a halt.
Britain and Norway were and are among the most maritime nations, their boats will be the best in the Western world and they will therefore dominate trade. Britain will be a trade partner with Southern Europe, a key central point geographically. Spices and goods will be imported. Briton metalwork and agriculture a major export as well as whales from Norway. Nordo-Britannica will be rich, especially in our time, with Norway and Scotland's rich oil deposits and Britain's abundant coal. There will also be great colonization.
Iceland - Iceland will be colonized, just like in our timeline, by Norway.
Americas - The Vikings actually found America through Canada, by crossing ice. The Brits were pioneers in America. Combine both and we have mass colonies in America.
Canada - See above - Vikings don't mind the cold!
India - The Brits did it in our timeline so why not here?
Greenland - Same as Iceland basically - After all, Denmark has been assimilated.
British Colonies in Africa - Same reason as India.
Australia - Goodbye, criminals. You can roast in the lush sun whilst we freeze our butts off!
Other places - My geography isn't the best.
SEE ABOVE + Both poles, because we're epic at skiing!!! So yeah, we would probably be really good at maps