Rule, Britannia!

[A Terribly Harmful Name]

Stop making it look like there are no certainties. British dominance over the Sea was a gradual but firm process, beginning with 1588 and reaching its culmination in the Seven Years War. After 1763 none could challenge them on the Sea, Napoleon tried but the precedents were so unfavourable that he failed as expected - and this situation continued well up to the XX century.

That's dominance, because maritime dominance means necessarily commercial, and thus economic dominance. Britain only truly began to forego it after their peak in 1850, first by repealing the Corn Laws, then by being steadily outmatched in industrial production by continental powers and the United States. But it was a 200 year period when they practically ruled the waves.

I had always thought it was more to do with bands of peasants beating the undisputed nobility on the field of battle.

A myth. People try to portray Agincourt as some sort of Marxian class struggle where the "proletariat" left victorious. In fact there were as many nobles scattered among the "peasants" as there were proportionally nobles in the French army; it was a common practice.

And the yeoman class was hardly a bunch of peasants with pitchforks. If anything, and by the standards of the Middle Ages, they were rather middle class property owners.