EU2 newbies :rofl: It feels like 2002 all over again...
You can get explorers/conquistadors based on real historical figures. This means you'll get a shitload of explorers as Portugal in the 15th century, a shitload of explorers as Spain in the 16th century.... etc. To get this to work, play nations like Spain, Portugal, France, England, Holland or Russia
You can also get them by event, as any country, only by having the right sliders. The easiest to get is the conquistador.
The third best way is to get into a war with Spain/Portugal in the 1520s, take their capitals then profit...
Check in /randomevents.txt
And you can fire them whenever you want, at least that's what I do.
That's called cheating, btw...