Final answer:
Tiberius succeeded Augustus as emperor in 14 AD and became the second emperor of the Roman Empire, marking the beginning of the Julio-Claudian Dynasty.
Step-by-step explanation:
Successor to Augustus
The heir who actually succeeded Augustus as emperor in 14 AD was Tiberius. Tiberius was the stepson of Augustus, and by the latter's arrangement, he received the power of a proconsul and a tribune from the Senate just before Augustus's death. Under Tiberius's rule, which lasted until 37 CE, the Roman Empire continued the traditions set by Augustus, and the dynasty that followed is often referred to as the Julio-Claudian Dynasty due to the blending of the Julian and Claudian families.
After Tiberius, the lineage continued with Gaius (also known as Caligula), who was Tiberius's grandnephew and adopted son, followed by Claudius, and later by Nero, the last of the Julio-Claudian line. Each of these emperors had their strengths and weaknesses, marking an era of both competence and despotism in Roman history.