Resource: http://www.sparknotes.com/shakespeare/titus/section1.rhtml
After the death of the Emperor of Rome, his two sons, Saturninus and Bassianus, ask the masses to determine who should succeed to the throne. The first invokes his natural rights as the first-born son, the second calls upon his virtue and graciousness. They are silenced by the Tribune of the People, Marcus Andronicus, who announces that the people of Rome have elected to the throne Titus Andronicus, a great general who has spent the last ten years and lost twenty-one sons vanquishing Rome ‘s enemies. Titus enters to great fanfare, trailed by four living sons and two in coffins; he brings with him the captives Tamora, Queen of the Goths, her three sons, and Aaron the Moore. Despite a desperate plea from Tamora, Titus orders, following Roman custom, that Tamora’s oldest son be ritually sacrificed in exchange for Titus’s own dead offspring.
Marcus offers Titus the scepter of Rome on behalf of the people, but Titus refuses it on account of his age. Instead, he states that Saturninus should be emperor because he is the eldest son; Saturninus returns the favor by taking Lavinia as his empress. Bassianus revolts against this, claiming that Lavinia is betrothed to him. He spirits her away, with the aid of Lavinia’s remaining brothers Lucius, Mutius, Quintus, and Martius. When Mutius intercedes with Titus on behalf of his fleeing sister, Titus strikes him down and kills him. It is only after his other sons plead with him that Titus even allows Mutius to be interred in the family tomb.
Publicly humiliated by the loss of Lavinia, Saturninus announces that he will instead take Tamora as empress. The new empress slyly advises him to accept the apologies of Titus and his sons, secretly promising Saturninus that she will help him find another day to exact revenge on the Andronici. The new emperor closes Act 1 by declaring it a love-day and inviting everyone to the court for a feast. Titus offers to organize a hunt for him the next day, and Saturninus accepts.
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