Yes, slavery has existed since ancient Greek and Roman times. In ancient Greece, slavery was an integral part of society and economy, with slaves making up a significant portion of the population. Slaves were often captured in wars or purchased from slave traders and were used as domestic servants, agricultural workers, and laborers in various industries. Slavery was also prevalent in ancient Rome, where slaves played a crucial role in household maintenance and agricultural labor. Slavery was accepted and justified in both societies based on social, economic, and philosophical beliefs of the time.