Complex sentence: Venice was involved in the Crusades almost from the very beginning; 200 Venetian ships assisted in capturing the coastal cities of Syria after the First Crusade, and in 1123 they were granted virtual autonomy in the Kingdom of Jerusalem through the "Pactum Warmundi".
Split into simpler sentences: Venice was involved in the Crusades almost from the very beginning. In 1123 they were granted virtual autonomy in the Kingdom of Jerusalem through the "Pactum Warmundi".