Complex sentence: One or two men were killed and much more were injured or captured from both sides during a skirmish between Tancred and Baldwin's retainers, which was the first occasion when crusaders fought against each other.
Split into simpler sentences: One or two men were killed and much more were injured or captured from both sides during a skirmish between Tancred and Baldwin's retainers. This was the first occasion when crusaders fought against each other.