Complex sentence: In contrast to regular counties, which were ruled over by counts, marches were ruled over by a Marquess (English), a Marquis (French or Scots) or nobles with corresponding titles (other European states).
Split into simpler sentences: In contrast to regular counties, which were ruled over by counts. Marches were ruled over by a Marquess (English), a Marquis (French or Scots) or nobles with corresponding titles (other European states).