So, my second ideology event I get is the one where you get the more powerful Elemental building, +35bc/turn if you build it. And I haven't built my central bank yet. I find the right planet with a +3 wealth tile and finish the elemental. Since I'm going to get this cash influx, I go out and buy the Mercenary transport which lets you invade worlds pre-War age. I hurry up and invade a nearby Minor, before they orbit any ships. Haven't finished the central bank yet. But guess who did: the minor race.