Hadrian
In 136 an ailing Hadrian adopted Lucius Aelius as his heir, but he died suddenly two years later. In 138, Hadrian promised to adopt Antoninus Pius if he would in turn adopt Marcus Aurelius and Aelius' son Lucius Verus as his own eventual successors. Antoninus agreed, and soon afterward Hadrian died at his villa near Tibur.