Short answers, pulled from the story.
Maximinus Thrax was a Roman emperor who ruled from 235 to 238. He is historically significant as the first emperor to come from neither the senatorial nor the equestrian class, and his rise to power in 235 is identified as the beginning of the Crisis of the Third Century, a 50-year period of instability and civil war that nearly destroyed the Roman Empire.
Maximinus was commander of the Legio IV Italica when Emperor Severus Alexander was assassinated by his own troops at Moguntiacum (modern Mainz) in 235. The Pannonian army elected Maximinus emperor, the Praetorian Guard endorsed him, and the Senate reluctantly confirmed the choice.
Maximinus was born around 173, most likely in Moesia Superior or Moesia Inferior, based on the historian Herodian and the chronicler Syncellus. His precise ancestry is debated; historian Ronald Syme rejected claims of Gothic heritage as anachronistic, while scholar Bernard Bachrach argues the Historia Augusta may have drawn on a legitimate third-century source. His family name Gaius Julius suggests they received Roman citizenship during the Julio-Claudian era.
Maximinus was assassinated in approximately May or June of 238 by soldiers of the Legio II Parthica while his army was besieging Aquileia. His son and his chief ministers were killed at the same time. He was halted at Aquileia after the city closed its gates against him, and his troops grew disaffected during the prolonged siege.
In 238, a senatorial revolt in Africa led to the successive proclamation of Gordian I, Gordian II, Pupienus, Balbinus, and Gordian III as emperors in opposition to Maximinus. Gordian I and Gordian II fell quickly when the governor of Numidia, Capelianus, opposed them with the III Augusta legion. The Senate then elected Pupienus and Balbinus as co-emperors, who in turn made Gordian III caesar. After Maximinus was assassinated, the Praetorian Guard killed Pupienus and Balbinus, leaving Gordian III as sole emperor.
The Historia Augusta claims Maximinus stood eight feet and one finger tall, approximately 2.4 metres, but scholars consider this figure an exaggeration and note it is attributed to Cordus, one of several apparently fictitious authorities in that work. His contemporary Herodian described him as being of colossal size with no obvious comparison among trained athletes or barbarian warriors. Ancient imagery depicts him with a prominent brow, nose, and jaw, features some historians associate with acromegaly.