The undisputed truth is, that Bavarian knigts were those, who soluted Kopány "uprising" (I am quite sure that uprising is not the right expression). But Slavic mercenaries? A mercenary is someone who get paid for a battle or for army service for some time and than leave. But those Slovaks who fight on St. Stephans side were definitely not mrcenaries. They were the nobles with their feudum=hereditary territory and with their own millitary force. They were those who enabled Stephens court to survive, until his wives kinsmen arrived. They (Chunt, Poznan…) could decided also different way and support the claims of Polish ruler Boleslaw, but history would be diametrally different by such conclussion.