Complex sentence: Coins were generally supported by the city state authorities, who endeavoured to ensure they retained their values regardless of fluctuations in the availability of whatever base precious metals they were made from Greece the use of coins spread slowly westwards throughout Europe, and eastwards to India.
Split into simpler sentences: Coins were generally supported by the city state authorities, who endeavoured to ensure they retained their values regardless of fluctuations in the availability of whatever base precious metals they were made from. From Greece the use of coins spread slowly westwards throughout Europe, and eastwards to India.