Read the time line. A timeline. A key shows purple for Western Empire and Green for Roman Empire. Purple entries include a bar showing a span from 27 B C E to 180 C E PAX ROMANA, 306 Constantine become Emperor, 480 C E The Western Empire Fell. 44 B C E The Roman Empire was founded. 80 C E The Colosseus was built. 121 C E Hadrian's Wall was built in England to keep out enemies. What does the colored bar represent? The first event a continuous event a chronological event the most important event