In the spring of 168 war broke out in the Danubian border when the Marcomanni invaded the Roman territory. This war would last until 180, but Verus did not see the end of it. In 168, as Verus and Marcus Aurelius returned to Rome from the field, Verus fell ill with symptoms attributed to food poisoning, dying after a few days (169). However, scholars believe that Verus may have been a victim of smallpox, as he died during a widespread epidemic known as the Antonine Plague. Despite the minor differences between them, Marcus Aurelius grieved the loss of his adoptive brother. He accompanied the body to Rome, where he offered games to honour his memory.