You can't argue that the best way to win is to bet on both sides.

The Rothschild patriarch (Meyer Rothschild) sent each of his five sons to a prominent European commercial centre in order to found branches of the family banking empire;

Take the story of Nathan Rothschild of Britain made a huge sum of money on the stocks after the battle of Waterloo. If Napoleon won that battle , it would be his brother James Mayer de Rothschild in France who would be hailed the financial genus
https://en.wikipedia.org/wiki/James_Mayer_de_Rothschild

If the Germans won WWI, the Austrian branch of Rothschild bank would probably become bigger than the British branch
https://en.wikipedia.org/wiki/Rothschild_banking_family_of_Austria#Family_members