The Romans built an extensive network of over 310,000 km of roads, known as the via Appia or Appian Way, which connected their territories and allowed for the spread of Latin. They also developed a codified legal system called the Twelve Tables in 450 BCE, which established basic legal procedures and punishments. Latin became the dominant language of the Roman government, legal system, education, and Catholic Church for over a thousand years and still influences modern languages like English through words and phrases used in medicine and law.