With the French. Lore has it they did it over dinner, sketched the lines on a napkin!
haha, King Hussien of Jordan originally was supposed to be the king of Arabia, but he ticked off the wrong people there and got booted, so Saud got it and Hussein got Jordan!
None of these were royalty, just families with connections that were utilized against the Ottamans. The Kurds as a group also were a big assist, but as would become a pattern (GHW Bush in the 90s, Trump now), they keep getting, well, royally screwed after they were used.