Complex sentence: Anastasia was the daughter of Roman Emperor Constantius Chlorus and Flavia Maximiana Theodora, and half sister of Emperor Constantine I. He proposed marrying her to form an alliance with Bassianus; however, Bassianus was found to be plotting against Constantine and the marriage was called off.
Split into simpler sentences: Anastasia was the daughter of Roman Emperor Constantius Chlorus and Flavia Maximiana Theodora, and half sister of Emperor Constantine I. He proposed marrying her to form an alliance with Bassianus. However, Bassianus was found to be plotting against Constantine and the marriage was called off.