Complex sentence: His call was at first poorly recieved among the ruling families of Europe, but by 1200 an army of approximately 35,000 soldiers had been assembled under Boniface of Montferrat.
Split into simpler sentences: His call was at first poorly recieved among the ruling families of Europe. But by 1200 an army of approximately 35,000 soldiers had been assembled under Boniface of Montferrat.