A vassal was a person who swore allegiance and homage to a lord. In exchange for this, he got property consisting of an estate or estates from which he could get income as the serfs who lived there gave him part of their crop or rent money. If the lord who did this was a king, then he would receive oaths of allegiance and homage from all the more important lords, dukes, earls or counts, and barons. He might also receive oaths from knights. The more important lords received similar oaths from lesser nobles and knights. Some of these received oaths from lesser people yet.